Forget the cold-stored, air mile-laden specimens you can buy in shops, these summer fruits are in a different league when they come fresh from the plot. Get clued-up with our guide to getting started with strawberries this month – and what to do for the next 12
Supermarket shoppers might be accustomed to watery, flavourless strawberries (no wonder given that they’ll have spent days in storage) but it’s hard to beat the flavour of a juicy, mouth-watering crop straight from the plot. Fortunately, they are one of the easiest and most reliable fruits to grow and ideal for raising either in the open ground or in containers on the terrace. Most strawberries produce a single crop between late May and late July and they are classified as early, mid or late season depending on when they ripen during this period. There are also perpetual varieties available, which can be used to extend the season by producing fruits from August to the first frosts.
If you already have strawberries growing on the plot, then there’s plenty that can be done in July. As well as harvesting the tasty fruits of mid and late season varieties, new plants can be produced by pegging the newly-formed runners (trails of growth which spread out over the soil surface) into small pots sunk into the ground. For grow-your-owners who have yet to get started with strawberries, it’s also possible to buy and plant cold-stored runners outside and, because they can fruit within 60 days, you will still get a small but worthwhile crop this autumn.
Strawberries perform best when grown in a sunny and sheltered part of the plot and the soil needs to be reasonably fertile and freedraining – avoid natural frost pockets at all costs. To ensure the plants thrive, it’s important to prepare the ground about a month before planting. Start by digging and forking over the soil to remove any weeds or debris – which could otherwise interfere with the growth of your crop and can harbour pests and diseases – then use a fork to incorporate plenty of well-rotted compost into the earth. Finally, the surface should be raked-over several times to create a fine and level tilth ready for planting.
The lifespan of a strawberry plant is three to four seasons and, to ensure the highest yields, they should be replaced with new ones at the end of this period.
The best way to foster the replacements is by using runners: in early to midsummer, established plants naturally send out thin, elongated and groundhugging stems. These are runners – the ends of which will naturally root in the soil while still attached to the parent plant. To propagate some new specimens, sink a few 7.5cm diameter pots into the ground (with the rims just proud of the surface) around the strawberry plants and fill them with moist cuttings compost. When runners appear, position the end of each one over the centre of a pot (with the base touching the compost) and hold in place with a small wire hoop. Afterwards, remove any that are not being utilised for propagating purposes so the established plant doesn’t waste any energy on them. After six weeks or so, the runners will have filled the pots with roots and they can be severed from the parent and used for planting either immediately or the following spring (they can be stored in a cold frame, with compost kept lightly moist).
Perpetual varieties don’t produce many runners but can be propagated by division in the early autumn. Lift a mature plant and cut it into two or three smaller clumps (with at least three shoots each) before replanting them. Do this every second year, as quality deteriorates more quickly than with standard strawberries.
Strawberries are usually purchased as pot-grown plants or barerooted runners – either way, make sure yours are certified as pest, disease and virus-free. The ideal time for planting cold-stored runners is from March to July – these plants will fruit around 60 days after planting. Ordinary bare-rooted runners are planted in mid-autumn (October time); they will have been grown in the open ground, recently certified as problem-free and then lifted and dispatched. The autumn plants will fruit the following season. Pot-raised plants can be planted at any time of year but spring, late summer and autumn tend to suit them best – the same goes for home-raised specimens (from runners).
For the best results, bare-rooted strawberries must be planted so that the ‘crowns’ (the base of the plants from which the leaves appear) are at (or just above) ground level. Too deep and the growing point will be smothered by the soil and may rot; too high and the roots may be exposed at the surface. To give the plants the best chance of establishing in the ground, lightly soak the root balls first before planting 35–40cm apart, then firm-in and water well. Pot-grown strawberries should be planted so that the root balls are buried to the same depth as in their original containers. If you have more than one row of plants, these should be spaced at 90cm intervals.
In smaller gardens, it may be easier to raise your crop in large containers – special pots known as strawberry barrels are available for this purpose. These are made from terracotta, wood or plastic and have lots of cup-shaped planting holes arranged spirally around the sides. Fill them with moist John Innes Number 3 compost before allocating a strawberry plant to each compartment and placing in a sheltered, well-lit corner of the plot. During the spring and summer, container-grown plants must be watered regularly and given a dose of liquid fertiliser (Ken Muir strawberry feed is a good choice) every week once flowers start to appear. Stop once the first fruits turn pink in colour – overfeeding will cause lush leaf growth to be produced at the expense of anything edible.
For strawberries planted in the open, once they are in the ground it’s essential to keep the area free from weeds and to make sure the soil doesn’t dry out, especially when the fruits are starting to swell. The plants should be given a dose of fertiliser in the spring and again after they have been rejuvenated, as well as being watered regularly (aim to keep the soil damp, but not saturated).
When the fruits appear a few months later, they can be ruined by mud splash and rotting due to contact with wet soil. To help prevent these problems, it’s a good idea to place a fabric strawberry mat (available from Marshalls) around the base of each plant – this will also act as a moisture-retaining mulch.
Alternatively, tuck a few handfuls of fresh straw under each plant and rest the leaves, flowers and fruit trusses on this material.
The young fruits are often targeted by birds, so it may be worth pushing short sticks into the ground in the four corners of the bed (so the tips are just above the top of the plants) and securing bird-scaring tape between them. It will vibrate and ‘buzz’ in the slightest breeze, scaring away hungry tweeters. Strawberry plants growing in containers are more easily protected by simply draping a sheet of netting over the top (something you shouldn’t do with an entire bed because birds will likely get trapped underneath).
Keep the ground around your plants free from weeds and remove any debris, such as fallen leaves, as it can harbour slugs and other nuisance pests
For an advanced crop of fruits, now's the time to cover early-season varieties with cloches. Prepare the ground for planting new strawberries.
Prepare the ground and plant new strawberry specimens. Give any established plants a muchdeserved feed with an organic fertiliser.
Harvest mid and late season fruits and keep the plants well watered. Propagate new specimens from runners. Rejuvenate the plants when they have finished fruiting by applying a good-quality feed. Plant new strawberries outside.
Rejuvenate strawberry plants by cutting them back when they have finished fruiting and applying a feed. Harvest the fruits of perpetual varieties. Sever runners that have been rooted in pots from the parent plants.
Harvest the ripe fruits of perpetual strawberry varieties. Sever any runners that have been rooted in pots from their parent plants.
Rejuvenating Strawberry Plants
To keep strawberries in good condition and encourage healthy new growth, the plants should be revitalised after harvesting. Start by removing any old straw and mixing the material into the compost heap. Alternatively, take away the strawberry mats and clean them before storing in the shed for use the following season. Once this has been carried out, use a pair of sharp shears to cut off all the old growth 10cm above the crowns – any runners that are spreading over the ground need removing unless they are being used to raise new plants. Afterwards, weed the site thoroughly and give the plants a feed with an organic fertiliser. New growth will soon emerge and this will form the basis of the next strawberry crop.
Related Forum Topics
Strawberries: Varieties To Try
A traditional and very reliable variety which crops from mid-June to early July with few problems. The fruits are bright red, juicy and flavoursome.
A perpetual strawberry producing most of its fruits in the late summer and early autumn. An excellent choice for small plots because it is prolific, fruits over a long period and does well in hanging baskets.
This is a late cropper (it ripens in late June and July) which is relatively disease-free. The plants stand upright, which ensures the fruits are held clear of the soil, and thereby reduces the risk of rot taking hold.
One of the earliest varieties to ripen, this plant produces large, glossy and juicy fruits in late May and June. Alternatively, the plants can be covered with cloches in late winter and then picked in mid-May.
Mara des Bois
A perpetual strawberry that produces a crop of rich-tasting fruits from August through to October. An excellent variety for containers because it is compact, fruits for a long period and is highly decorative.
This is a mid-season variety, which will ripen from mid-June until around mid-July. It is a prolific and heavy-cropping plant and the glossy, bright-red strawberries it produces are deliciously sweet.
Forcing an early crop
One of the benefits of growing an early-season strawberry variety, such as ‘Mae’ is that the plants can be ‘forced’ to produce an advanced crop of fruits. They will be ready for picking in mid-May, a couple of weeks earlier than normal and often when strawberries are sold at premium prices in the supermarkets. The forcing process involves covering the plants with cloches (small, tent-like structures made from glass or plastic) in late winter. These create a warm and sheltered environment underneath and this encourages the plants to produce leaves, flowers and fruits much earlier than usual. Once the strawberries begin to flower, the sides of the cloches must be opened during the day, as this will allow insects to visit the blooms and pollinate them. If this is not done, fewer fruits will form. Remove the cloches when the fruits have been picked.