Grow your own veg box

Summer vegetables

Image: Tastes of summer, second week of July (clockwise from top left): potato ‘Cosmos’; tomatoes ‘Golden Cherry’ and ‘Gardener’s Delight’; bulb fennel ‘Zefa Tardo’; cucumbers ‘Flamingo’, ‘Prima Top’ and ‘Sunsweet’; beetroot ‘Boltardy’, courgettes ‘Sebring’ (yellow), ‘Genovese’ (pale green) and ‘Defender’ (dark green); garlic; carrot ‘Nantes Early’; onion ‘Radar’ (from sets); calabrese ‘Green Sprouting’; edible-pod pea ‘Sugar Snap’; dwarf French bean ‘Slenderette’; artichoke ‘Green Globe’.

Perennials

GLOBE ARTICHOKE This can be grown from seed, bought young plants or divided roots. It needs a well-prepared, fertile soil cleaned of all perennial roots and preferably in full sun.

Sowing indoors in January can provide plants for April which will crop in summer. Plant at 45x150cm (18x60in) or 100x100cm (39x39in).

After globes are harvested in summer, including the smaller secondary ones, prune or twist out the woody stem they grew on to make way for new growth from the base. Another small harvest often occurs in September, after which remove old flowering spikes again, as well as old leaves. This makes it easier to thin new shoots, leaving three or four new plants from the one root system. They will grow slowly through a mild winter, or lose all their leaves in a cold one, before fast new growth happens again the following spring.

‘Vert Globe’ (sometimes sold as ‘Green Globe’) is the standard cultivar, ‘Imperial Star’ is a refinement of it, and ‘Purple Globe’ gives a slightly smaller harvest of faintly coloured globes.

Annuals

BEETROOT A reliable, fast-growing vegetable offering many colours and flavours, beetroot often has more sweetness in freshly pulled roots than in bought ones, especially in early summer. Sowing is from April (or March in mild areas &/or with protection) to early July, direct in rows at 30x5cm (12x2in), or sow four seeds per module and plant out the small clumps 30x30cm (12x12in) apart. Fleece may be used to prevent birds pecking small leaves – usually this stops as plants grow – and harvesting is by twisting out larger roots to leave small ones for picking later.

One sowing may provide meals for up to two months, as large roots are still good to eat, just a little coarser in texture. The cultivar ‘Wodan’ F1 is good at remaining tender as it grows, ‘Boltardy’ is best for early sowings (it can be sown in early March in a greenhouse), ‘Sanguina’ is an excellent maincrop red beet, ‘Burpee’s Golden’ and ‘Chioggia Pink’ offer unusual colour and ‘Cheltenham Green Top’ is a sweet long beetroot for winter, usually sown in June.

CALABRESE This may be attacked by caterpillars of the cabbage white or cabbage moth butterflies. Covering plants with mesh should keep them out, as well as reducing flea beetle damage to the leaves, if the mesh is fine enough. Sowing both early and late can also reduce the damage, with first sowings indoors in early March for planting out at 35–40cm (14–16in) apart in beds or large containers and at 25x60cm (10x24in) in rows.

Covering early calabrese with fleece will both keep pigeons off and encourage faster growth, leading to first harvests by mid- to late June, when butterflies are normally not too numerous. Cut the large central dome when buds are slightly swollen, then after 10-14 days there should be the first of several smaller shoots to pick, growing lower down the stem. Harvests are more plentiful in wet summers and can be increased by watering in hot weather.

Hybrid cultivars such as ‘Belstar’ and ‘Fiesta’ tend to have larger heads compared to ‘Green Sprouting’, the strength of which is an abundance of longer, smaller shoots. ‘Romanesco’ types have pretty, paler heads more akin to a small cauliflower.

Broccoli for spring, often purple flowering, is sown from May to early July; plants grow larger than calabrese and offer plentiful small heads from late winter to mid-spring.

CARROTS These can be sown from March until mid-summer. Dry spring weather is best for early growth, in 30cm (12in) rows across beds and ideally with one plant every centimetre (half inch) or so. In containers, scatter seed thinly and sprinkle some compost on top. Thick sowings make more leaf and less root.

Keep on top of weeds, as early growth is slow, then once a few shoulders of root appear above the soil or compost, some early harvests can thin out the crop and encourage future growth; keep pulling larger roots as needed or carefully loosen them with a pointed trowel.

Winter carrots can be sown as late as mid-June and this avoids earlier damage from carrot root fly. Covering with fleece or mesh and sowing resistant cultivars are useful defences, and some years the flies are not numerous. They re-emerge in autumn and may infect carrots from October, so it can be worth harvesting then to store carrots in a paper sack, somewhere cool and frost free.

Cultivars of summer carrots include ‘Early Nantes’ and ‘Adelaide’ F1; for some resistance to carrot fly there are ‘Flyaway’ F1, ‘Sytan’ F1 and ‘Resistafly’ F1, while for storing in winter there are ‘Autumn King’ types such as ‘Kingston’ F1 and old cultivars such as ‘James Scarlet Intermediate’ and long ‘Lisse de Meaux’. To enjoy unusual colours sow ‘Yellowstone’ and ‘Purple Haze’ F1, and for extra sweetness the choice includes ‘Sugarsnax 54’ and ‘Tendersnax’ F1. In containers, ‘Mini Finger’ grows well and has fine flavour.

COURGETTES As courgettes need warmth to grow well and are not frost tolerant, wait until April for sowing indoors and late May for sowing outdoors, especially when using expensive hybrid seed. Growth is fast and seedlings raised indoors are usually potted on to finish in an 8cm (3in) pot, before planting at 60cm (24in) spacing on beds, or 60x120cm (24x48in) in rows, or one plant in a 45cm (18in) pot.

Harvests begin a month or more after setting out plants, and courgettes want picking every two days, especially in hot weather, unless you want small marrows. Picking them large increases the weight of harvest, which should continue until the first autumn frost, having slowed down in September, partly because leaves are often covered in mildew by then. Container-grown plants require daily watering because growth is so rapid and large leaves tend to shed rain.

There is a wide choice of cultivars, each with different merits. ‘Defender’ F1 is productive in cooler summers, ‘Venus’ F1 makes a smaller plant, ‘Rondo di Nizza’ (‘Ronde de Nice’) produces round courgettes and ‘Black Forest’ F1 can be grown vertically but is not easy to support. Cultivars for striking yellow fruit, such as ‘Sebring’ and ‘Jemmer’ F1, tend to produce less courgettes.

CUCUMBERS Although these can be grown indoors or out, cucumbers are best sown indoors unless you can wait until August for the first harvest. Growth of young seedlings is highly heat dependent, so wait until early May, even for indoor sowing, unless you have a heated propagator. Start seedlings in small pots or modules and repot to an 7.5cm (3in) pot when the first true leaf is developing. If planted out in cold conditions, slug damage may result.

Plants need as much room as courgettes and are usually trained up a stake or string indoors, or trail over a large area outdoors, with fruit often hidden under leaves. Indoors, vertically growing cucumbers require sideshooting of new growth at each leaf axil where new fruits also form. If the shoots are not removed, a mass of leaves and poor-quality fruit, some on the ground, will result. Fruits are best picked before they swell in the middle and show any sign of yellowing, both of which indicate seediness.

Cultivars for indoor growing are usually all-female flowering hybrids to avoid the bitterness arising from fertilisation of fruit with male pollen. Seed is expensive and some good cultivars are ‘Flamingo’ F1 for long fruit and ‘Passandra’ F1 for shorter ones of 15cm (6in). Two reliable outdoor cultivars are ‘Burpless Tasty Green’ F1 and ‘Masterpiece’: they can crop into October if it is mild.

FENNEL, SWEET FLORENCE Fennel tends to flower (bolt) from sowing too early, before about mid-May. It matures best in moist conditions, so sowings in July that swell up in autumn rain often make the fattest bulbs, which are delicious baked, stir-fried or chopped raw into salad. Sow in rows 45cm (18in) apart and thin to 15cm (6in) between plants, keeping on top of weeds as early growth is delicate with long, thin leaves.

When plants become larger and more feathery, some leaf ends may be pinched off for use in seasoning and salads. As bulbs swell, watch closely for any tendency to elongate upwards, whatever size they are: once this happens, you need to harvest before flesh turns to fibre. Fennel resists slight frost but bulbs are damaged when the temperature goes below about -3°C (27°F).

Some good cultivars are ‘Montebianco’, ‘Romanesco’, ‘Rondo’ F1 and ‘Zefa Tardo’ although differences between cultivars are less marked than for other vegetables. Note that the herb common fennel and bronze fennel are closely related, but never make a bulb.

FRENCH BEANS These do need warm soil to germinate, so sow indoors from early May and outdoors from late May. Climbing cultivars need more work to support, but the beans grow clear of soil and slugs; dwarf beans crop more quickly and can be sown as late as early July, for cropping in September. Dwarf beans also grow well in containers, say three or four plants in a 45cm (18in) pot. In open ground, space them at 30x30cm (12x12in) in beds and 15x60cm (6x24in) in rows. Climbing beans need more room, for example 30cm (12in) between plants in a wigwam that can be walked around.

Harvests are better in hot summers, although plants also like moist roots to crop well. Once cropping begins, beans are best picked twice a week if you want them small and tender.

Choice of cultivar depends on your preferences: dwarf beans can be green (‘Slenderette’ or ‘Nomad’), yellow (‘Sonesta’) or purple (‘Purple Teepee’). Climbing beans have similar colour variations, can be flat or round and cultivars such as ‘Borlotto Lingua di Fuoco’ can also be left unpicked to gather in early autumn as dry pods for shelling out their delicious beans.

GARLIC To have larger bulbs (than when planted in late winter), garlic is best planted in early October. Break up bulbs and plant the largest cloves at 10x30cm (4x12in), in soil that has been cleared of summer crops such as beans, then spread some compost on top so that the cloves’ top ends are about 2cm (1in) below the surface. Keep them well weeded and enjoy watching them grow in any mild winter weather, then vigorously in spring for harvest in late June to early July, when tops are yellowing but still partly green.

Ease a trowel underneath the bulbs and rub soil off their roots, then lay them in trays under cover or hang in bunches to dry.

Two problems may be rust in dry springs, which makes for smaller bulbs, and white rot fungus from the soil infecting and eventually rotting roots and bulbs, which must then be removed off site: that patch of ground may then be infectious for several years.

There are many cultivars on offer with different qualities; you can also plant cloves of garlic from bulbs bought to eat, but the results are not always as reliable.

ONIONS These can be grown from seed or sets. Cultivars for overwintering, such as ‘Radar’ and ‘Senshyu Yellow’, are best sown in late August or planted as sets by mid-October. They overwinter as small plants, which may need some hand weeding, then mature in June, usually before onion mildew has become too prevalent. Spring-sown onions can be raised indoors or out, while a simpler way is to plant sets in late March for harvest in early August when the tops start to bend over. Pull bulbs out gently or, better still, carefully lift with a hand fork, and leave on the soil to dry, or lay them on staging in a shed if you have room.

Two diseases to watch out for are white rot (see garlic) and mildew, which is almost invisible at first: a light grey mould on leaves that then die prematurely. Bulbs can still be harvested, taking care not to break their neck so that the fungus cannot enter the bulb.

Cultivars for spring planting include ‘Centurion’ and ‘Sturon’ for globe-shaped bulbs, ‘Stuttgart Giant’ for flat ones, ‘Red Baron’ for red ones and ‘Walla Walla’ for large white bulbs to eat raw.

PEAS Garden peas grow best in spring and early summer. Sow indoors in small pots or modules from early March and sow outdoors in April, one seed every 3cm (1in) in rows 60–120cm (24–48in) apart, depending whether you are growing dwarf or tall cultivars. Dwarf plants crop earlier and can be supported on small branches of hazel, for example, to keep peas off the soil and away from slugs. Tall cultivars can grow more than 2m (6.5ft) high and need support from netting or tall stakes with small branches and perhaps some string between them for tendrils to hold on to.

Potential problems include mice eating the seed (sow indoors with a mousetrap), pigeons eating leaves of young plants (use fleece for two or three weeks), pea moth laying eggs on baby pods and their maggots burrowing into peas (sow early and grow dwarf peas and keep covered with mesh), and mildew on leaves (avoid sowing after April as pea mildew is most prevalent in late summer).

Cultivars include ‘Feltham First’ or ‘Misty’ for 40cm (16in) high early plants, ‘Greenshaft’ for a 75cm (30in) maincrop pea, which resists mildew, and ‘Alderman’ for large yields off 150cm (60in) high plants. Mangetout peas offer edible pods and sugar snap types offer sweet peas in edible pods – try ‘Sugar Ann’ for 75cm (30) high plants and ‘Tall Sugar Snap’ for vigorous plants up to 2m (6.5ft) tall.

POTATOES These grow fast and offer high yields as long as the ground is well manured or composted, and providing they stay clear of blight. In warm, wet summers this can be hard to achieve, even for cultivars offering some resistance, but Sarpo potatoes have the ability to stay mostly healthy, and first early cultivars often crop before blight arrives.

Choice of cultivar is important, resulting in the harvest dates listed here from March plantings. First earlies (best for small gardens) crop from late May to early July; second earlies such as ‘Cosmos’ crop from July to early September; and maincrops are ready from September onwards, best harvested by mid-October before slugs do too much damage. Tubers harvested before plants are mature – often revealed by the end of flowering – are paler and have little skin. Salad cultivars such as ‘Charlotte’ and ‘Pink Fir Apple’ offer smaller yields of extremely waxy tubers.

Plant 30–45cm (12–18in) apart in rows 60cm (24in) apart and earth up soil around plant stems as they grow, to prevent light from turning tubers green.

Harvest after flowering or when plants lose their healthy lustre and leaves start to yellow. Potatoes can be grown in half-full plastic sacks of compost, with more compost added as they grow, and regular watering. After harvest, tubers kept cool and dry should store for many months, maincrops especially.

TOMATOES Like potatoes, tomato plants are prone to blight, so growing them outdoors is usually best in dry summers. Planting indoors is more reliable and gives higher yields, whether in soil, growing-bags or large containers.

Sow seed indoors with gentle heat from February to mid-March, repot when roots need more room and nutrients, allow 45–60cm (18–24in) when planting, and stake determinate (tall-growing) cultivars – which will also require sideshooting. Bush cultivars are less work, but their fruit may be eaten by slugs at ground level.

Choose cultivars according to whether you want tall or bush plants, and your taste and size preferences. Cherry tomatoes crop well in cooler summers, red ‘Sakura’ F1, orange ‘Sungold’ F1 and ‘Gold Nugget’ F1 have superb flavour. ‘Rosada’ F1 is a tasty small plum tomato, ‘Ferline’ F1 has good colour and flavour in its medium-sized fruit (also a little blight resistance), and ‘Marmande’ is a reliable cultivar for beefsteak fruit, which tend to struggle unless it is a hot summer. There are numerous heirloom cultivars with exciting fruit quality and of variable merit to grow. You can keep and resow their seeds, unlike the F1 hybrids which do not grow true to cultivar.

For even more detailed information, see our vegetables A-Z section