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Gardening advice

RHS Online: Gardening for All
 

Advice

Gardener's Calendar - June

Fruit, vegetable & herb garden
Flower garden
Glasshouse, conservatory and houseplants
Trees, shrubs, roses, climbers and hedges
Lawns and meadows
Ponds
Wildlife gardening
Garden structures
Gardening for children

Top 10 jobs

1. Hoe borders regularly to keep down weeds
2. Be water-wise, especially in drought-affected areas
3. Pinch out sideshoots on tomatoes
4. Harvest lettuce, radish, other salads and early potatoes
5. Position summer hanging baskets and containers outside
6. Cut lawns at least once a week
7. Plant out summer bedding
8. Stake tall or floppy plants
9. Prune many spring-flowering shrubs
10. Shade greenhouses to keep them cool and prevent scorch

June's weather

Find out what to expect

Glossary of terms

Blanching
Cordon
Hoeing
June drop
Pinching out
Pricking out
Set
Truss

Fruit and vegetable garden

AppleFruit

Keep wall-trained fruit, especially stone fruit, well watered during fruit set and fruit development. Use rainwater or recycled water wherever possible.

Mulching fruit will help them to retain moisture around the roots.

Water tree, bush and cane fruit thoroughly every seven to 10 days during dry spells.

On indoor grape vines allow only one flower truss to develop on each main lateral coming off the central rod. Any others should be removed. Keep flowering laterals short, pinching out their tips of at two leaves past the single flower truss. Non-fruiting laterals can be kept a bit longer, pinching out the tips after five leaves have formed. Any sideshoots branching off the main laterals should be stopped at one leaf.

Thin out bunches of grapes on dessert grape vines to encourage decent-sized fruit. You should aim for one bunch per foot of rod (i.e. 10 bunches on a 10ft rod). Wine grapes do not need thinning.

Wall-trained plums and cherries can be pruned this month. If pruned in winter or spring (while still partially dormant), they run the risk of getting silver leaf disease. Any branches coming out away from the wall should be removed entirely. Pinching out tender shoot tips, plus any sideshoots coming from the main stems, will prevent the trees from putting on too much green growth, re-directing their energy into fruit production. If you need replacement shoots for bare areas of an established wall-trained tree, or if you are forming a new tree, then select and retain one or two strong shoots arising at the base of the bare area, to train into these areas. Selecting two suitable shoots means that you have insurance in case of the first shoot being damaged.

For wall-trained sweet cherries, pinch out the growing tip of each branch, once it has grown six new leaves. After fruit picking, the shoots can be cut back again, removing half of the current year’s new growth, and removing any overcrowded or unhealthy looking stems at the same time.

For wall-trained ‘Morello’ and acid cherries, prune out entirely any fruited shoots, removing all of this year’s new growth. But be careful not to remove any unfruited new shoots, as it is these that will produce fruit next year. Instead, tie them in so that they are easy to pick the following year.

Thin fruits on wall-trained peaches and nectarines. When they are marble-sized, thin to leave one fruit every 10cm (4in), and then thin again to 15-20cm (6-8in) when they reach walnut size.

Wait to thin plums and gages until the natural fruit drop has occurred, usually around the start of June. Then thin in two stages: in early June to 4cm (2.5cm/1in gaps between fruits), and then in late June to 7.5cm (3in) between fruits.

Shorten leaders and sideshoots on over-vigorous wall-trained apples and pears, to weaken their growth and divert their energy to fruit production rather than shoot growth.

Wait to thin apples until after the 'June drop'. Pears only need thinning if fruit set is heavy. Thinning can help improve the size and quality of the crop, and can prevent a cycle developing of ‘one good year followed by one bad year’ (known as biennial bearing).

Gooseberries can also be thinned - this will result in larger, dessert-quality fruits. The unripe thinnings can still be used in cooking.

Tie-in the new canes of blackberry and other hybrid berries to prevent wind damage.

Pinch out tips of new fig shoots once they have five leaves.

Put straw around strawberry plants to prevent soil splashing on to the fruit. Strawberries grown through black plastic do not need strawing.

If a small number of new strawberry plants are needed, you can peg down the runners that develop on existing plants, to encourage them to root along the stem. If a large number of new plants are needed, it is better to remove the runners before they start to creep along the ground. Leaving too many of them will sap energy from the existing plants and reducing yields. Removed runners can be potted up separately. You could even keep a couple of plants aside, pinching off any flowers to encourage them to concentrate on producing green shoots and runners only, for saving and potting up.

Any strawberry crops previously kept under glass, fleece or cloches, should now be uncovered (or the greenhouse doors opened fully), to allow access for pollinating insects.

Harvest rhubarb stems until the end of the month, but leave crowns ‘forced’ earlier in the year to recover.

Hoe off or pull out raspberry suckers appearing between the rows.

Control weeds to prevent them competing for moisture and nutrients. Hoe regularly between rows on hot days to make sure the weeds dry up and die.

Pest & disease watch

Keep an eye out for early aphid attacks, and deal with them appropriately, either by squashing small colonies, or by using pesticides on larger infestations. Remember that very few pesticides have approval for use on edible crops. Derris and pyrethrum are often good choices, but always check the label first for confirmation of approval, safety and effectiveness.

Blackcurrants are vulnerable to big bud mite (affected buds appear larger than normal). The mites can spread blackcurrant reversion virus. Affected plants must be dug up and disposed of in the rubbish, or by burning. You may wish to grow resistant varieties such as ‘Farleigh’, ‘Foxendown’ or ‘Ben Hope’.

Raspberry beetle can damage crops of raspberries and loganberries. Treat with an appropriate insecticide as soon as the first pink fruits are seen.

Keep alert for gooseberry sawfly damage and the raised red blisters of currant blister aphid.

Dead shoots on tree fruit may indicate a number of disease problems. Check for signs of apple and pear canker, bacterial canker, and blossom wilt.

Hang pheromone traps in apple trees to help reduce codling moth numbers, if you have not done so already. You will need one trap for every three to five trees. A similar trap is available for red plum maggot on plums.

Don’t be too worried if your pear tree leaves come up in small pale blisters. This is probably due to the pear leaf blister mite. Although there are no effective pesticides available to amateur gardeners, the damage is not as severe as the plant's appearance may suggest. Infested trees can still produce a good crop of pears.

American gooseberry mildew can appear as a brown crust over the leaves and fruits of gooseberry bushes. Spraying with fungicides containing sulphur or myclobutanil is usually effective, but you may wish to grow a more resistant variety like ‘Invicta’.

Never spray pesticides once blossom has opened on fruit crops. They will kill the pollinating insects that you rely on for your crops. When carrying out any spraying operation, take care to spray early in the morning when fewer pollinating insects are about - you only need to kill the pests, not the beneficial insects.

Apples and pears may need spraying against scab, where this has got out of hand in previous years. Fungicides containing mancozeb or myclobutanil are suitable choices.

Look out for powdery mildew, especially during warm dry spells.

Keep watch for signs of cane spot or spur blight on blackberries and hybrid berries. Ensure that any fungicides used have approval for use on edible crops. Products containing sulphur, myclobutanil or mancozeb are often good choices, but always read the label to check for approval and safety before using.

Reduce numbers of rotten strawberries by tucking straw mulch, strawberry matting or similar around the plants, to prevent the fruits from touching the soil or getting too damp. Covering the whole bed with netting will also reduce bird damage. Remove any mouldy fruit and leaves promptly to prevent spread of infection.

Net soft fruit as they begin to ripen, to protect them from birds.

RadishesVegetables

Harvest indoor cucumbers regularly to encourage more fruit to set.

Early peas may be ready for harvest. Cut off the tops of the plants, leaving the roots in the ground to conserve valuable nutrients to the soil. Peas and other legumes can ‘fix’ nitrogen from the air.

Harvest salad onions, salad leaves, beetroot and radishes as they mature.

Overwintered Japanese onions can be harvested when the tops start to fall over. Leave the bulbs to dry in a sunny spot outside, or in a airy shed if rain is forecast. This will allow the skins to harden, and the bulbs to store better.

If you have started off crops early under cover, and live in a mild part of the UK, you could be harvesting early crops of courgettes, small summer squashes, sweetcorn, calabrese, pak choi, kohl rabi, French and broad beans and carrots. Spring or early summer cabbages and cauliflowers planted last year will also be ready for cutting.

Harvest spring lettuce, spring cabbage, salad onions and radishes. Continue with successional sowings of these and other salad crops. Herb crops such as basil, coriander and parsley can also be extended with successional sowings.

Early potatoes may begin to be ready for harvesting. Many are ready when the plants come into flower. Take care when digging them up to insert your fork some distance away and to lift the soil carefully. Otherwise you may pierce and damage the tubers.

Continue to earth-up potatoes not ready for harvest (unless planted through black plastic). Earthing-up is the drawing up of soil around the stems of the plants, leaving just 5cm (2in) of shoot uncovered so that the plant has enough foliage to continue growing. Potatoes can also be grown in containers.

Continue with successional sowing of salad crops, beetroot, Chinese cabbage, pak choi and radish, to ensure an even supply over the season. In hot weather, leafy salad crops may do better when sown in partially shady sites. Hot dry weather can lead to bitter tasting leaves.

Plant out tomatoes if this has not already been done. Train them up canes or string, and remove sideshoots from cordon tomatoes. These sideshoots develop in the leaf axils (i.e. between the stem and leaf), and if allowed to develop will sap the energy of the plant and reduce the quality of the yield. Small sideshoots can easily be pulled off with a thumb and forefinger, and can be easily rooted to obtain more plants. When four flower trusses have formed, pinch out the growing point just above the highest truss.

Celeriac and self-blanching celery can be planted out this month. A well-prepared site with lots of organic matter dug in is essential. Planting celery in blocks aids the blanching process, as does placing a strip of plastic around the edge of the block to exclude some light and further improve the pale colour and sweetness of the blanched stems.

Outdoor ridge cucumbers can be planted out this month. They benefit from a site that has been enriched with lots of organic matter to help retain water. Pinch out the tip of the plant when it has made six pairs of leaves, to encourage sideshoot and cucumber formation. Feed regularly with a liquid tomato feed, following the instructions on the packet.

Sow French, broad and runner beans, peas, squash, sweetcorn, and outdoor cucumbers directly into prepared beds outside.

French beans are best sown in traditional rows, 45cm (18in) apart, at 15-22cm (6-9in) spacing.
Sweetcorn works best planted in blocks, at 45cm (18in) spacing, with two seeds per hole. The strongest seedling can be selected later, and you will have the safety of knowing there is a fall-back in case of slug damage. Any seeds sown earlier under cover can now be planted out into the same block pattern.
Runner beans benefit from well-prepared ground with lots of well-rotted manure and organic matter dug in. They need to be planted alongside suitable supports (often a frame or wigwam of bamboo canes tied together with twine) for the shoots to twine around and grow upwards.

Strings stretched along the sides of broad bean plants will support them and prevent them flopping once pods develop.

Peas need staking with pea sticks, netting, or pruned twigs from the garden.

Courgettes, marrows and pumpkins can still be sown outdoors in early June. Encourage good fruit set by hand pollinating. Push the male flowers (distinguished by the lack of swollen stem/young fruit behind the petals) lightly into the female flowers.

Plant out other vegetables sown indoors earlier in the season, including winter brassicas and sweet peppers. Peppers can only be planted out when all risk of frost has passed. The gaps between winter brassica plants can be used for quick-maturing catch crops, perhaps radishes or gem lettuces, as brassicas take time to grow into their eventual spacing.

Although most winter brassicas need to be sown earlier in the season, you can still sow turnips now for an autumn crop, as they are best lifted while still young and sweet. Sow them in drills 15cm (6in) apart, and thin them as soon as they are large enough to handle, to leave one plant every 10cm (4in).

Plant out artichokes that were previously sown under cover. They are tall handsome plants, and the steamed unopened flower buds are considered a delicacy. They can be grown as perennials (in which case they need 90cm spacing), or as biennials (45cm spacing is sufficient).

Witloof chicory can be sown this month, in drills directly outside, to have some ready for forcing next winter, when other salads are scarce. Forcing is a similar process to blanching, but provides additional heat to promote the growth of pale, sweet stems very early or late in the season.

Asparagus is a perennial vegetable. Harvest spears from established plants for six to eight weeks from May into the early summer. Do not harvest spears from crowns less than two years old. After harvest and flowering, it is a good idea to feed them so that they have sufficient energy for next year’s crop.

Control weeds to prevent them competing for moisture and nutrients. Hoe regularly between rows on hot days to make sure the weeds dry up and die without re-rooting. Weedkiller is usually inappropriate as there is a high risk of it killing or damaging your crops as well as killing the weeds.

Pest & disease watch

Keep an eye out for asparagus beetles, which are black, red and yellow, and their creamy-black larvae. Pick them off stems and foliage by hand.

Look out for blossom end rot on tomatoes and peppers. This is not actually a disease, but the symptom of nutrient, calcium, deficiency that occurs when water supply is erratic. Regular watering and appropriate growing media should prevent too much damage.

Pinch out the top of broad beans once the lowest flowers have set. This will help prevent aphid attack.

Watch for the small holes flea beetles make on brassica seedlings. Water well to help them continue to grow, despite the pest damage.

Keep carrot fly off carrots by covering them with a fine woven plastic mesh like Enviromesh. Just make sure that the corners are well tucked in or buried to prevent them breaching this defence.

Slugs pose a threat, and slug controls are necessary now, as always.

Pick yellowing leaves off brassicas promptly, to prevent spread of grey mould and brassica downy mildew. Do not compost such material, but put it in the rubbish, burn it, or bury it deeper than 60cm (24in) depth.

Damping off of seedlings can be a problem with sowings both outside and in modules or containers. Clean equipment and, where necessary, use of fungicides (e.g. Bio Cheshunt Compound) can help to control this problem.

Cover young brassica crops with nets to protect them from pigeons.

Ensure that crops remaining in the ground, new sowings under cloches, and any stored vegetables, are well protected from mice.

Herbs

Crops such as basil and coriander can be sown every two to four weeks until the end of June, especially in cooler regions where spring is later. Parsley can be slow to germinate, especially in warm dry weather, so don’t attempt to sow this herb once summer weather has arrived.

Control weeds by hoeing between garden plants and by hand weeding containers. Weed infested clumps may need lifting to disentangle weeds from the plant roots.

Pest & disease watch

Remove any mouldy or yellowed leaves promptly, to prevent spread of grey mould and other fungal diseases.

Giving plants adequate spacing will help to improve air circulation and reduce the risk of fungal problems.

Look out for pest problems once the weather warms up. Vine weevil can be a pest of container-grown plants.

LilyFlower garden

Plant out summer bedding and seed-raised plants, if not already done so. Make sure they are well watered in and keep moist during dry weather.

Plant out cannas and dahlias once danger of frost has passed.

Finish planting out gladioli.

Gaps in herbaceous borders are best filled with annual bedding at this stage in the season, delaying any planting of permanent perennials until the autumn or the following spring. One exception is wood anemones (e.g. Anemone blanda or Anemone coronaria), which take about three months to flower after planting. The rhizomes are best planted now, after an overnight soaking, 5cm (2in) deep in a suitably moist but free-draining soil or compost with lots of added leaf mould or organic matter.

It is not too late to direct sow a few fast growing, late-flowering hardy annuals such as Calendula, Godetia and Clarkia.

Perennials such as Alcea (hollyhock), Delphinium and Lupinus can be sown directly into drills outside once the seed heads have ripened and started to split and scatter seed naturally. If garden space is limited and you do not have a nursery bed or space in the vegetable plot, then you can sow them into pots and place them in a cold frame or by the base of a sheltered wall in filtered sunlight.

Thin out direct sowings of hardy annuals. This is best done in two or three stages at fortnightly intervals. Final spacings should be between 10-20cm (4-8in), using the upper limit for tall or spreading plants, and the lower limit for smaller plants.

Prick out indoor sowings when they are large enough to handle without damage, potting them on and then planting them out once they are robust enough to resist slugs, snails and the outdoor climate.

If you want to grow your own spring bedding for next year, many common choices (including wallflowers, pansies, and Bellis perennis) need to be sown between May and July in order to flower next spring, as they are biennials (which live for two years, and flower only in the second year, as opposed to annuals, which live and flower for one year only).

Polyanthus primulas are best sown only when temperatures are reliably warm, as they need a constant temperature of around 15°C (60°F). A sheltered cold frame in June or July usually provides the right environment for their germination and growth.

Winter bedding plants for the following winter can also be sown from May until July. Attractive choices include ornamental cabbages, kales and winter pansies.

Spreading and trailing plants such as the annual Lobularia (sweet alyssum), and the perennials Alyssum, Geranium, Heuchera and Aubrieta, can become tatty and patchy. Trimming them back after flowering encourages fresh growth and new flowers.

Cut back dead bulb foliage if not done already. It is important to wait until the foliage dies down naturally, as cutting back too early can lead to blindness next year.

Cutting back clumps of spring-flowering perennials such as Helleborus, Pulmonaria and Doronicum can encourage a fresh flush of foliage, which is more attractive than the old, mildew-covered or spotted foliage. Plants will stay more compact and will flower better next year.

Cut back and deadhead Oriental poppies after flowering. Cutting them right back to ground level will stimulate growth of fresh new foliage, and perhaps even some new blooms. Mulching and feeding will help to support this new growth.

Euphorbias looks a lot better if spent flowers are removed, cutting the flowered stem back to ground level. This can be especially important with Euphorbia amygdaloides var. robbiae, as old stems of this cultivar are particularly prone to powdery mildew when grown in dry soils.

Deadhead flowering perennials such as Lupinus and Delphinium to improve their appearance and promote a second flush of flowers later in the season.

Pinch out the leading shoots on plants such as Chrysanthemum and Helianthus to encourage bushy plants. However, if tall thin sprays are preferred, they can be left un-pinched, perhaps removing a few buds (known as ‘disbudding’) to encourage larger blooms.

Divide Primula (primroses) after flowering, planting them in a nursery bed until they are ready for planting out again in the autumn, for a display the following spring.

Divide hostas as they come into growth.

Lift and divide overcrowded clumps of bulbs after they have finished flowering.

Lift clumps of forget-me-not once the display wanes, and before too many seeds are released. They can become invasive if left unchecked.

Stake tall perennials to prevent wind damage to flower spikes.

Sweet peas need training and tying in to their supports to encourage them to climb and make a good display.

Liquid feed containerised plants every two to four weeks.

Keep tubs, hanging baskets and alpine troughs well watered. Use collected rainwater, or recycled grey water wherever possible.

Tubs can be planted up with summer bedding if not done already. You can always keep some horticultural fleece handy to cover pots in the event of a cold night or late frost.

Hellebore seed can be harvested once the seed heads have ripened (i.e. when squeezing the pod causes it to split and release dark coloured seeds into your hand). Seed needs to be sown immediately, while fresh, and need a winter’s cold season in order to break their dormancy in order for germination to occur. Do remember that seed grown plants will differ from the parent plant - you may be pleasantly or adversely surprised at the results!

Perennials that are showing new shoots from the crown can be propagated via basal stem cuttings. Shoots 8-10cm (3-4in) high are cut from the parent plant with a sharp knife. Sometimes a piece of root can be taken with the cutting (which speeds establishment), but stems can be cut without root, and then dipped in hormone rooting powder before striking into growing medium, as for softwood cuttings.

Take cuttings from garden pinks (Dianthus). They can be pulled off the parent plant by pulling with thumb and forefinger while holding a suitable non-flowering shoot four pairs of leaves from the tip. Treat as softwood cuttings.

Pot on plants showing signs of being rootbound. You can tip out the rootballs of unhappy looking containerised specimens, to see if they are indeed potbound or if they are suffering from some other problem.

Hoe borders to prevent annual and perennial weeds from spreading and seeding themselves.

When gardening on wet soils work from a long plank of wood rather than treading on the bed to avoid compacting the soil.

Tackle bindweed when it appears in a border. You can try digging it out, but you must remove all the white roots. Alternatively, try painting the leaves with Tumbleweed Original Extra Strong Gel, according to the instructions on the bottle. Or insert bamboo canes at regular intervals and once the weed has climbed up the cane, it can be spot treated with a weedkiller containing glyphosate.

Pest & disease watch

Inspect lilies for the scarlet lily beetle whose larvae can strip plants in days.

Vine weevil larvae can be a serious pest of containerised plants, and become active this month. Tip out the rootball of suspect plants, and inspect for the creamy, orange-headed maggots, which tend to curl up into a ‘C’ shape. There are various chemical and biological controls available.

Aphids multiply rapidly in summer. Remove early infestations by hand to prevent the problem getting out of control. Aphids can transmit viruses, as can other sap-sucking insects.

Continue to protect lily, delphiniums, hostas and other susceptible plants from slugs and snails.

Hellebores can develop hellebore leaf spot on old leaves. Cutting back tatty foliage can prevent this disease spreading to new growth coming up from the base.

Remove dead leaves from around the basal rosettes of alpine plants to prevent rotting.

CactusGlasshouse, conservatory and houseplants

Move conservatory plants, such as Cymbidium, Yucca, Ficus and Citrus outdoors during warm days but bring in if cold nights are expected.

Pot up houseplants showing signs of being rootbound or topdress large containers with fresh compost.

Pot on any Begonia, Gloxinia and Achimenes plants that you started off earlier in smaller pots, but which are now large enough to re-pot in the next size up.

Try growing on plug plants in your glasshouse. They are a relatively cheap source of large numbers of plants, and can be ordered and grown on quickly if you didn’t get round to sowing seed in good time earlier this season.

Don’t forget to give glasshouse plants more space as they put on new growth. This will help to prevent disease, and to contain early pest infestations.

Check plants at least every few days, to see if they need watering. Seedlings will need daily attention. Use rain, grey or recycled water wherever possible.

Continue to prick out and pot on new seedlings and cuttings.

Harden off half-hardy bedding plants that were started off under cover.

Train the new stems of passion flowers and other climbers over frames or on horizontal wires.

Apply shade paint to the outside of the glass or use blinds on sunny days to prevent temperatures from soaring.

Open doors and vents on greenhouses to increase ventilation on warm, sunny days.

Damp down the floor of the glasshouse regularly on hot days, to increase humidity levels. This benefits plant growth and also reduces the risk of pest problems such as glasshouse red spider mite.

Pest & disease watch

Vine weevil larvae can be a serious pest of containerised plants, and become active this month. Tip out the rootball of suspect plants, and inspect for the creamy, orange-headed maggots, which tend to curl up into a ‘C’ shape. There are various chemical and biological controls available.

Regularly inspect plants, and also the structures of the greenhouse and conservatory, for glasshouse red spider mite, whitefly, thrips and other pests. Careful attention to the undersides of the leaves, and to each plant in turn, can spot early infestations that would otherwise be missed. Control with approved insecticides and biological controls, and hang yellow sticky traps to help monitor numbers of flying pests.

Brush up fallen compost and debris, and pick off dead leaves from plants. This will help prevent pests and disease spreading.

Foot and root rots can affect young plants grown from seed and cuttings, especially those grown under glass. Clean equipment and, where necessary, use of fungicides such as Bio Cheshunt Compound can help to control this problem.

ShrubTrees, shrubs, roses, climbers and hedges

Cut back tender shrubs such as Penstemon, Caryopteris and hardy fuchsias after danger of frosts has past.

Clip evergreen hedges such as privet (Ligustrum), box (Buxus) and Lonicera nitida if needed. If they are not too woody, shredded clippings can be added to the compost heap.

Thin out new shoots on trees and shrubs that were pruned in winter to stimulate growth. Remove crossing stems and prevent overcrowding of new growth.

Thin out new shoots on trees and shrubs pruned in winter if necessary to prevent overcrowding.

Prune out any remaining frost damage from affected evergreen shrubs.

Prune flowering shrubs such as Deutzia, Kolkwitzia, Weigela and Philadelphus after they have finished flowering. If this job is left too late, the new growth put on after pruning may not have sufficient ripening time to flower well next year.

Evergreens such as Viburnum tinus can also still be trimmed this month.

Prune deciduous magnolias once the plant is in full leaf. If this is done in winter, when the tree is dormant, dieback can occur, and pruning in late winter or spring can result in bleeding. Midsummer is therefore recommended.

Rhododendrons can be lightly pruned after flowering. More severe pruning should wait until the following early spring.

Prune overcrowded, dead or diseased stems of Clematis montana once it has finished flowering. Untangling the stems can be fiddly, but once you can see where you are cutting, you need not worry about pruning this plant - it will take even hard cutting back very well.

Young mimosa trees (Acacia dealbata) can be cut back once all risk of frost has passed. Mature trees respond less well to hard pruning.

Prune wall-trained pyracanthas, removing any shoots coming out from the wall, and shortening other new growth to about 8cm (3in). This encourages spur formation, and increased flowering relative to green growth.

Remove any reverted green shoots on hardy variegated evergreens, to prevent reversion taking over.

Twining climbers (such as honeysuckle and Clematis) need regular tying in and twining around their supports.

Tie in climbing and rambling roses as near to horizontal as possible. This will restrict sap flow causing more side-shoots to grow along the length of stem. Therefore more flowers will be produced.

Hybrid tea roses can be disbudded, removing all smaller buds from the cluster that forms at the shoot tip, leaving the largest central (or ‘king’) bud to develop into a large, show-stopping bloom.

Ensure newly planted trees and shrubs do not dry out. Water with rain, grey or recycled water wherever possible.

Loosen any tree ties that are digging into the bark, or could do so soon as the trunk girth expands.

Take softwood cuttings of deciduous shrubs, including Caryopteris, Forsythia, Kolkwitzia, lavender and rosemary if not done last month.

Take softwood cuttings of many deciduous shrubs, including Fuchsia, Hydrangea macrophylla, Philadelphus and Spiraea.

Layering is a good way to propagate climbers and lax-stemmed shrubs. Layers should root by next spring, especially if attention to watering is given during dry weather. Examples to try include Philadelphus, Wisteria, Akebia and Lonicera.

Sprinkle fertiliser around perennials, shrubs and roses.

Water around the crown of tree ferns, especially newly planted ones.

Dig out tree and shrub suckers. If sucker removal is difficult, sever the root to isolate the sucker from the parent tree and then carefully treat the sucker with ammonium sulphamate (as found in products such as Amcide or Root Out).

In wet areas, you can still plant containerised trees and shrubs. But if summer rainfall is scarce, then planting is best avoided. You would be wiser to wait until autumn, when the weather will work with you rather than against you to ensure the successful establishment of your new trees and shrubs.

Pest & disease watch

Check roses for signs of blackspot, aphids and leaf-rolling sawfly damage.

Viburnum beetle grubs start nibbling holes in the leaves this month, giving plants a tattered appearance. Inspect V. tinus and V. opulus regularly and spray or pick of the grubs by hand.

Inspect sick looking box and holly trees for signs of blight.

Phytophthora root rots can cause die back on mature trees and shrubs. Wet winter weather followed by a hot spring and summer can encourage this problem on susceptible woody plants.

Check for damage or cankers on deciduous trees.

Caterpillars, aphids and other fly pests can all be problematic at this time of year. Early infestations can be managed by hand removal, but approved insecticides are necessary for more serious attacks.

LawnLawns and meadows

Regularly mow lawns to keep them in shape - removing 'little and often' is the key to a good quality sward.

Mow pathways through areas of long grass to allow access to other areas of the garden.

Cut the lawn edges with a half-moon edging iron to ensure they are neat and well shaped. Grass growing over the edge can be trimmed with edging shears.

Use the half-moon edging iron, or a spade, to create a 7.5cm (3in) ‘gutter’ around the lawn edge. This will prevent grass from creeping into the border from the main lawn.

Add grass clippings to the compost heap in thin layers (too much grass all at once is likely to be very wet and poorly aerated, resulting in smelly slime rather than compost).

Apply a high nitrogen summer lawn fertiliser if not done last month to encourage a healthy-looking lawn.

Move garden furniture and other objects regularly to allow grass to recover and prevent yellow patches.

Ensure new lawns (either from turf or seed) do not dry out during hot weather, as turves will shrink if allowed to dry out, and fail to knit together.

Don't worry about weed seedlings in newly seeded turf. These will disappear once regular mowing begins. Start with a high cut, lowering the height of the mower blades gradually.

Troubleshooter

During periods of prolonged dry weather, you could help by keeping your lawn a little longer than usual, and even investing in a mulching mower. Mulching mowers shred the grass clippings very finely and then blow them into the lower layers of the turf, where they act like mulch to help the lawn retain moisture. Because the clippings are fine, the end result is not unsightly, especially later in the season when the lawn gets very dry, and the mulch helps to keep it green rather than brown.

If moss is a problem, choose a combined fertiliser and mosskiller when feeding the lawn.

Selective weedkillers are available for lawns, which will kill the weeds but not the grass or any naturalised bulbs (providing they've died down). However, they will kill wild flowers.

Disperse dry worm casts with a hard-bristled broom.

Molehills can be a problem in rural areas. Traps are the most effective way to deal with this problem.

PondPonds

Tidy up plants in the bog garden, and mulch with composted bark or garden compost.

Thin out, cut back or divide excessive new growth on aquatic plants.

If not done last month, feed large aquatic plants by inserting slow-release fertiliser tablets well below soil level around the base of the plant. Water lilies are big feeders.

Keep ponds and water features topped up.

Clean out pond filters.

Once new plantings have established, you can start to stock new fishponds with fish. Start stocking and feeding when the water is warm. Don’t leave fish sitting in plastic bags full of water - get them in to the pond as soon as possible so that they have a sufficient supply of oxygen. Feeding fish little and often is best, to prevent the excess food causing unwanted algal blooms.

Avoid introducing goldfish into the wildlife pond, as they will upset the pond's natural balance.

Cover or use safety grills on ponds in gardens where young children play.

In colder areas where spring is later, you can still plant new aquatic plants. Vigorous specimens should be planted in aquatic plant baskets to contain them. Top the surface with a layer of gravel to prevent the fish from stirring up the compost, and insert slow-release fertiliser tablets into the compost so that they are well below the surface. Small plants in baskets can be raised up on bricks when first introduced then slowly lowered to the bottom of the pond as they increase in size.

Troubleshooter

Remove blanket weed by twirling around a rough stick. Skim off floating weeds such as duckweed with a net. Leave weeds on the pond side for 24 hours to allow trapped creatures to return to the water before adding to the compost heap.

Grille coverings (either simple meshes or bespoke features) can protect young children from accidents. The size of the mesh can be judged in order to prevent hazard, but to also allow access for wildlife, and to preserve the aesthetic appeal of the pond.

Monitor the water level of your pond, as defects in liners and concrete structures may have developed and need repairing.

New or recently cleaned ponds can suffer problems with algae. Providing some shade can help reduce this problem. Ironically a covering of Lemna (duckweed) can provide sufficient shade to help suppress the algae until cultivated aquatic plants establish sufficiently to suppress the duckweeed’s proliferation. Other helpful measures include filling the pond with rainwater rather than with tap water, avoiding contamination of the pond with soil or compost (as these encourage algal growth), and taking care to remove plant debris from the water promptly.

Wildlife gardening

Jobs for the month

Bird life

Don’t let bird-‘flu fears stop you from enjoying the bird life in your garden. You can watch the behaviour of garden birds without coming into any physical contact with them, and as long as you wear gloves, an apron or overall, and a paper face-mask while performing such tasks as re-filling the bird feeder, scrubbing the bird bath, or attending to domestic flocks, you will be keeping the risk at such a low level as to be negligible. Obviously, if you live within a high-risk area where the H5N1 strain of bird ‘flu has been found, or in a restricted zone as designated by DEFRA, then you should take extra precautions as advised (please see www.defra.gov.uk/animalh/diseases/notifiable/disease/ai/).

Migrant summer-visiting birds from other continents are among those now common in British gardens. You may see willow or garden warblers, housemartins, swifts and swallows.

Avoid peanuts and large chunks when putting out food for the birds, as there is a risk that large pieces could be fed by adults to their fledglings, and this could result in choking. Safe foods include wildbird seed mixes (but not those containing peanuts or dog biscuit); black sunflower seeds (the birds will remove the outside casing, and the inner seed is soft); mild grated cheese; sultanas, raisins and currants (best soaked overnight); pinhead oatmeal; apples, pears and other soft fresh fruit; mealworms and waxworms. Alternatively, you can buy fat balls from many garden centres and bird food suppliers. This is an easy alternative, and you can be confident that you will be doing no harm.

To maximise the numbers of different bird species that you attract to your garden, it is a good idea to cater to their different feeding habits. Hanging bird feeders attract species such as tits, finches and sparrows. There are many models available, designed to help keep out rats, cats, pigeons and squirrels, or to fit onto walls, windows, windowsills and balconies. Bird tables attract robins, house and tree sparrows, doves, pigeons, bullfinches, greenfinches, chaffinches and bramblings. Food scattered on the ground attracts blackbirds, thrushes, dunnocks and wrens.

Hanging bird feeders are best sited over a paved or decked area, which can be regularly swept clear of debris. This may help to reduce problems with squirrels and vermin, if they prove a nuisance.

Bird tables are best sited a few feet clear of cover or high vegetation, so that cats and other predators cannot launch themselves onto unsuspecting feeding birds. They can be quite close to the window or patio, as many birds seem to get used to human activity, and are unlikely to be put off by coincidental human activity.

A birdbath can be a vital source of drinking water for birds. Ensure that yours is kept topped up. Models are available to attach to windows, walls and sills, if you are limited for space. Do be aware of hygiene: change the water regularly and scrub the bath out with a mild detergent (available from bird food suppliers) to help prevent the spread of disease.

Insects

Bug life is thriving this month, and should be encouraged. Without insects and other invertebrates, there would be no birds and mammals, and many flowers would fail to pollinate, set seed or produce fruit. Bugs help to keep each others’ populations in check, avoiding large build-ups of unchecked pests.

Damselflies and dragonflies are out in abundance. They are usually spotted near ponds and lakes. Damselflies have a lazier, zig-zagging pattern of flight, whereas dragonflies take a faster and more direct flight path.

Pond skaters and also water boatmen can be seen skating on the pond surface in search of food.

Gardens with some nooks and crannies, and a few areas where debris is allowed to accumulate (perhaps a woodland area or a meadow within a more formal design), are often more insect-friendly than those composed entirely of paving, pots, lawn and bedding displays.

Bee homes are now widely available. Initial reports suggest that nesting boxes for colony-forming bees (such as bumble and honey bees) are not always effective, but homes for solitary bees (such as mason bees), made from tubes and tunnels in boxes, are more successful. They are also attractive. Models with a backing are more successful than those open at both ends. This kind of bee house is easy to make at home. Even a tin can filled with straws will do the job. South-facing positions, hanging at chest height or above, are best. Bees usually colonise these homes in spring, hibernating over winter to emerge the following spring. The boxes can be left out over winter, or taken down and stored in a safe place to avoid bees being eaten by predators.

Put out log and twig piles made from old prunings and felled trees. These provide valuable shelter for wildlife, and can be made into attractive features by planting up with ferns, primroses, or other suitable plants. A site well away from the house should ensure that unwanted creepy crawlies do not stray into domestic rooms.

Piles of slabs or rockery stones will act as a suitable wildlife habitat, as will old bales of straw, hay or prunings.

Corrugated iron or plastic laid on the soil can provide ‘tunnel’ hiding places for small reptiles and mammals looking for shelter and warmth.

Mammals and amphibians

Many garden mammals have given birth to young, and you may spot baby wood mice, shrews or voles, and even fox or badger cubs (most likely in the evenings).

Bats are breeding this month, often in eaves, or behind the weatherboarding of south-facing buildings. Why not put up a bat box on a sunny wall? Many bat species are garden-friendly, eating the midges and tiny insects that cause annoyance on summer evenings.

Young litters of hedgehogs and badgers are being born, and you may see or hear their parents foraging for food at night. Hedgehog and badger food is available for sale. It is not a good idea to feed hedgehogs with bread and milk, as this is not their natural diet. Good quality cat or dog food, or raw minced meat mixed with raw egg make good alternatives.

Use a wildlife-friendly brand of slug pellets to avoid harming predators that eat the affected slugs.

Tadpoles are developing their adult ‘frog-legs’ and can be vulnerable to predators as they emerge from the water’s edge to seek shelter among the marginal pond plantings.

Plants for wildlife

As a very general rule, single flowers attract more insects than double blooms. Bear in mind that insects can be attracted to a particular plant for its nectar (Sedum spectabile), its pollen (Lavatera), the shelter it provides (many ornamental grasses and other species) or its suitability for breeding (many native trees, shrubs, climbers, or weeds, such as the common nettle). A variety of insect-friendly planting fulfilling all these needs is likely to attract many more insects than is a mass planting of a single species fulfilling only one.

Hedges, even non-natives and conifer hedges, are a very good resource for wildlife, providing shelter, nesting sites and food for wildlife. Deciduous trees, particularly natives like oak, or coppiced hazel, are excellent for wildlife. Some insects that happily feed from a variety of plants are more selective about their breeding territory, and show a preference for native plants. Deciduous trees also support so much more plant life underneath their canopy, with bulbs, annuals and perennials thriving in their dappled shade. This is not the case underneath dense coniferous planting.

Be less frequent with your hedge trimming to provide greater shelter and food for insects and birds. Don’t trim any hedge that has birds nesting in it. You can get the growth under control once the fledglings have flown the nest and it is left abandoned.

Don’t deadhead roses that produce hips. The colourful hips are both decorative and a useful source of food for wildlife.

If you have left a suitable part of the garden untouched as a wildlife area, then cut back the nettles quite hard to encourage fresh young growth. This will provide suitable egg-laying places for a new generation of butterflies as they hatch out of their pupae. Tortoiseshell, peacock, comma and red admiral butterflies will all lay eggs on young nettle leaves.

Spring-flowering meadows can be cut and mowed this month, after the bulb foliage has died down naturally. Scything and removal of clippings is all that is necessary, but closer mowing will allow the area to be used as rough lawn for the rest of the summer. Meadow cuttings have traditionally been used for making hay, but they can just as well be used on the compost heap - just be sure to remove any pernicious weeds and those that are actively flowering first, so that they don’t germinate in your compost.

Recently sown perennial meadows should be mown about six to eight weeks after sowing, when they reach a height of 5-10cm (2-4in), and then again every couple of months in their first year, removing the cuttings each time. This helps to control weeds and to toughen up the meadow plants. A stronger healthier meadow will be the end result.

Recently sown annual wildflowers do not need mowing. Just leave them to develop and flower, but be aware that will only last one year, and will die back completely in the autumn.

Garden structures

Use a stiff-bristled brush or pressure washer to remove algae from paths. A proprietary algae killer may help.

Remove dirt and algae from walls, paving and patios. Pressure washers can be rented if necessary.

Check and repair pergolas, arbours and arches if needed.

In dry spells, you can treat timber structures with wood preservative and stain. Only do this in a well-ventilated space, to reduce the risks to your lungs and eyes. Make sure you use appropriate products. Creosote, for example, is no longer legal (link to page on products taken off the market).

Go through your shed and remove any old, out-of-date garden chemicals. If in doubt of how to dispose of them, your local authority tip should be able to help. You can check our list of chemicals removed from the market for up-to-date information.

Gardening for children

As well as being able to take part in many of the above activities, here are some extras especially for them.

Continue to involve children in harvesting and sowing edible crops. Food crops tend to fascinate and provide valuable education about where our food comes from, as well as widening tastes and broadening palates.

Children and teenagers with an artistic bent may enjoy planting out bedding plants to a design they have developed themselves - a bit like colouring in but on a garden scale, and perhaps something that could double as a school project. They then have the subsequent responsibility for watering and picking over their bedding plants, and watching how the picture changes as the plants grow and develop. Choosing drought-resistant bedding plants is more sensible in our changing climate and will reduce the amount of watering needed.

On hot days, water is always fun to play with in the garden, and children can be tasked to damp down the greenhouse floor and water pot plants (once responsible enough not to drown them or splash the leaves). Teach them the value of water and correct watering and not to waste this precious commodity.

Older children may enjoy the ‘macho-ness’ of using garden machinery. Machinery such as lawnmowers and hedge trimmers are reasonably sage and can legally be used by children of age 13 and older - with close supervision. Again teaching them the correct and safe use of powered tools is essential.

 

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