Water frequently while new plants are establishing. Also water during dry periods in the growing season. Water from the bottom as water from overhead can rot the crown and fruit.
During the growing season, give strawberry plants a liquid potash feed – such as a tomato feed – every 7 to 14 days. In early spring, apply general fertiliser such as Growmore at a rate of 50g per sq m (2oz per sq yd).
In a heated greenhouse or conservatory, it is possible to bring forward flowering by several weeks, so long as the temperature does not go above 16°C (61°F), because this will inhibit flowering. You will also need to hand pollinate the flowers.
As fruits start to develop, tuck straw underneath them to prevent the strawberries from rotting on the soil. Otherwise use individual fibre mats if these are not already in position. The straw or matting will also help to suppress weeds. Weeds that do emerge should be pulled out by hand.
After cropping has finished, remove the old leaves from summer-fruiting strawberries with secateurs or hand shears. Also remove the straw mulch, fibre mat, or black polythene, to prevent a build-up of pests and diseases.
Expect strawberry plants to crop successfully for three years before replacing them. Crop rotation is recommended to minimise the risk of an attack by pests and diseases in the soil.
Strawberries are so versatile – they just need sun, shelter, and fertile, well-drained soil. Avoid areas prone to frost and soils that have previously grown potatoes, chrysanthemums, or tomatoes because they are all prone to the disease verticillium wilt.
Buy plants from a trustworthy supplier so that the cultivars are what they say they are and the plants are disease free. Order plants in late summer so that they can be planted in early autumn. Strawberry plants bought as cold-stored runners should be planted from late spring to early summer and will fruit 60 days after planting.
Runners look like little pieces of roots with very few leaves. Don’t be alarmed, this is how they should look. You can buy runners from late summer to early spring, and they should be planted in early autumn, or early spring (avoid planting in winter when the ground is wet and cold). You sometimes also see strawberries for sale in pots (normally from late spring onwards) and these can be planted as soon as you buy them.
Strawberries are traditionally grown in rows directly into the garden soil – often referred to as the strawberry patch. Avoid windy sites which will prevent pollinating insects from reaching the flowers. In poor soils grow in raised beds, which improves drainage and increases rooting depth. Alternatively, try containers or growing-bags.
Strawberry plants can be grown under a tunnel cloche to produce an earlier crop by up to seven to 10 days. Place the cloche over the plants in early spring, but remove or roll up the sides when the plants are flowering to give pollinating insects access.
Strawberries in containers can also be grown in an unheated greenhouse, which encourages an even earlier crop, by 10–14 days. In a heated greenhouse or conservatory, it is possible to bring forward flowering by several weeks, so long as the temperature does not go above 16°C (61°F), because this will inhibit flowering. You will also need to hand pollinate the flowers.
Summer-fruiting varieties are the largest and most popular. They have a short but heavy cropping period over two or three weeks. There are early, mid-, and late fruiting cultivars cropping from early to mid-summer.
Perpetual strawberries – sometimes called everbearers – produce small flushes of fruits from early summer to early autumn. The crops are not so heavy as the summer-fruiting ones and the fruits are smaller, with the plants less likely to produce runners. Perpetual strawberries are useful for extending the season. To concentrate strawberry production in late summer and early autumn, remove the early summer flowers.
Measure out planting holes 35cm (14in) apart. Dig out a hole large enough to accommodate the roots. Trim the roots lightly to 10cm (4in) if necessary, then spread them out in the hole. Ensure that the base of the crown rests lightly on the surface. Planting at the correct depth is important: if the crown is planted too deeply it will rot; if it is planted too shallowly the plants will dry out and die. If planting another row, place it 75cm (30in) away. A fibre mat can then be placed around each plant, or you can plant through black polythene. Water the plants well.
Once the plant is at the correct depth, backfill the soil, keeping it off the crown and firming it around the plant using finger tips. If planting another row, place it 75cm (30in) away. Water the plants well. A fibre mat can then be placed around each plant, or you can plant through black polythene.
Glasshouse red spider or two spotted mite: Leaves become mottled, pale and covered in webbing, on which the mites can be clearly seen; leaves also drop prematurely.
Remedy: They thrive in hot, dry conditions, so mist plants regularly. Use sprays based on soft soap, plant oils or extracts. Use the biological control Phytoseiulus persimilis in the greenhouse.
Birds: Birds, especially pigeons, can cause an array of problems including eating seedlings, buds, leaves, fruit and vegetables.
Remedy: Protect the plants from birds by covering them with netting or fleece. Scarecrows and bird-scaring mechanisms work for a while, but the most reliable method of protection is to cover seedlings with horticultural fleece or mesh.
More info on Birds
Powdery Mildew: Appears as a white powdery deposit over the leaf surface and leaves become stunted and shrivel.
Remedy: Keep the soil moist, grow in cool locations, and spray using plant and fish oils or sulphur-based controls.
More info on Powdery Mildew
Grey mould: Can be a problem in densely sown crops, especially ‘cut and come again’ veg crops. Seedlings suddenly collapse. This is a problem normally in wet conditions, and is usually worse on weak or damaged plants. The mould usually enters through a wound but, under the right conditions, even healthy plants will be infected. You will see fuzzy grey mould on affected buds, leaves, flowers or fruit. Infected plant parts eventually shrivel and die.
Remedy: Sow thinly and when conditions are warm. Hygiene is very important in preventing the spread of grey mould. If you see it, remove the infected material and destroy. Grey mould is encouraged by overcrowding, so make sure you plant your seedlings, plants and squashes at the appropriate distance apart.
No fungicides are approved for use by amateur gardeners against grey mould. Products containing plant and fish oil blends may be used but are unlikely to have much impact.
More info on Grey mould
Fungal leaf spot: Irregular purple/brown spots surrounded by a yellow ring- the spotting spreads throughout the foliage especially in warm, humid conditions. The plant weaken when the infection is severe.
Remedy: Remove affected leaves and ventilate covered crops.
Pick strawberries when they are bright red all over, ideally during the warmest part of the day because this is when they are at their most tasty.
Eat them as soon as possible; they do not keep well, but some can be frozen or made into preserves.
Nigel Slater’s soft set Strawberry jam is easy to make and tastes of summer.
Simply impressive - this Strawberry and mascarpone tart is simple to make but looks impressive.
‘Aromel’ AGM: Pepetual - A cultivar popular for its delicious flavour.
‘Honeoye’ AGM: Early croppers - A darkish berry with excellent flavour. Can be susceptible to mildew. Fruits during early summer.
‘Cambridge Favourite’ AGM: Mid season - A traditional favourite, this variety can have a few disease problems but the fruit is juicy and possesses an excellent flavour.
‘Alice’ AGM: Mid season - One of the best midsummer strawberries with a sweet flavour and juicy texture with good disease resistance.
‘Elsanta’: Mid season - The most widely grown commercial cultivar, it has superb flavour and large yields of glossy, red fruit. Can be prone to disease.
‘Hapil’ AGM: Mid season - This mid-season cultivar produces heavy yields of light red fruits. Fruits are firm and have excellent sweet flavour.
‘Pegasus’ AGM: Mid season - A good, reliable cropper with excellent disease resistance, particularly to mildew and verticillium wilt.
‘Symphony’(PBR) AGM: Late season - Acultivar from Scotland with attractive, glossy, red fruit and excellent flavour. is hardy and has good disease resistance, although it can be susceptible to mildew
‘Florence’: Late season - A late summer strawberry with good disease resistance. The large, bright, glossy fruits have good flavour.
‘Mara de Bois’: Pepetual - Well liked for its crop of intensely flavoured fruit that is said to be reminiscent of wild strawberries.