Jobs to do in June

Now’s the time to plant out the last of the tender crops, including tomatoes and courgettes. Give support if needed, such as bamboo canes for runner beans or cordon tomatoes

Sowing and planting

Fruit

• Transplant outdoor melons under cloches, pinching out the growing point.
• Move forced strawberries outdoors.

Vegetables

• Continue sowing leafy crops, such as beetroot, lettuce, pak choi and radish. Leafy or salad crops are best grown in a part-shaded spot to reduce demand for water, and because hot dry weather can lead to bitter-tasting leaves.
• There’s still time to sow French and runner beans, peas, squash, sweetcorn, and outdoor cucumbers directly into prepared beds outside.
• French beans are best sown in rows, 45cm apart, at 15-23cm spacing.
• Sweetcorn works best sown in blocks with at least 45cm between holes, with two seeds per hole. Sow before mid-June. Any young plants raised under cover can now be planted out into the same block pattern.
• Runner beans need supports – often a frame or wigwam of bamboo canes tied together with jute twine – for the shoots to climb up. 
• Courgettes, marrows and pumpkins can still be sown outdoors in early June in southern England and south Wales.
• Although most winter brassicas need to be sown earlier in the season, calabrese, turnips and kohl rabi can be sown now for an autumn crop.
• Celeriac and celery can be planted out early this month. Add lots of homemade compost to the planting site.
• Outdoor ridge cucumbers can be planted out early this month. They benefit from lots of homemade compost to help retain water.
• Plant out vegetables sown indoors earlier in the season, including winter brassicas and sweet peppers. Wait until all risk of frost has passed before planting peppers. Plant them beneath cloches for best results. When to plant out tender plants >
• Gaps between winter brassica plants can be used for quick-maturing catch crops, such as radishes or gem lettuces.
• Plant out artichokes that were sown under cover. They can be grown as perennials, in which case they need 90cm spacing, or as biennials, for which 45cm spacing is sufficient.

Pruning and training

Fruit

• Continue training fan-trained trees.
• Pull off suckers appearing around the base of fruit trees.
• Pinch-prune figs.
• Thin out pears, plums, peaches, nectarines and apricots. Apple fruits should be thinned out at the end of the month.
• Tie new shoots of blackberries and hybrid berries out of the way. Once the current stems have fruited, these will be your replacement stems to train in.
• Summer prune red and white currants and gooseberries.
• Shorten newly planted raspberry canes once new shoots are produced.
• Summer prune kiwi fruit and indoor grapes.
• Thin out fruit of indoor grapevines to give large dessert grapes.

Prevention

• Check asparagus plants for asparagus beetle and remove them by hand.

• Pinching out the top of broad beans once the lowest flowers have set will reduce the numbers of aphids. A few aphids are nothing to worry about and support the food chain in your garden, including baby birds.
• Protect carrots from carrot fly by covering them with biodegradable fleece or a reused fine woven mesh like Enviromesh.
• Slugs and snails can damage newly planted seedlings, so carry out torchlight searches to relocate them away from new seedlings.
• Pick off yellowing leaves from brassicas promptly to prevent spread of grey mould and brassica downy mildew.
• Damping off of seedlings can be a problem both outside and in containers. Make sure your peat-free compost or soil is lightly moist but never soggy.
• Net cherries against birds and keep protection in place for all soft fruit.
• Look out for shothole (pictured below) on the leaves of stone fruit trees – a sign of possible bacterial canker infection. The shotholes themselves are nothing to worry about, but if you see amber-coloured gum oozing out of the trunk or areas of dieback, the tree may need replacing as it declines.

General care

Fruit

• Feed pot-grown fruit weekly with liquid seaweed.
• Peg down strawberry runners and remove cloches from outdoor strawberries once harvested.
• Water blueberries, cranberries and lingonberries regularly with rainwater. If butts run dry, use tap water sparingly.
• Water and feed indoor melons daily once they are established and plant into peat-free compost in containers or growbags in a greenhouse.

• Check soil moisture at finger’s depth and water fruit plants only when needed to avoid drought stress. Those that are in containers, against a wall or newly planted are most likely to experience drought stress.

Vegetables

• Regularly feed ridge cucumbers in containers with liquid seaweed, following the instructions given.
• Peas need staking with pea sticks, pruned garden twigs or reused netting.
• Continue to earth up maincrop potatoes.
• To build up the strength of asparagus crowns for long-term cropping, wait until the crowns are at least three years old before harvesting. If  you want to sample a few spears, this won’t harm the plant.
• Hoe off competing weeds between rows on hot days to avoid re-rooting.

• Look out for the sunken brown patches of blossom end rot on tomatoes. Aim to keep the compost or soil consistently moist with stored rainwater and stick to the instructions on your fertiliser pack to avoid overfeeding.