Helen Simpson, from the Mushroom Shed, tells you all you need to know about growing strawberries. She has also written articles about growing basil, brassicas, chilli, coriander, cucurbits, garlic, ginger & turmeric, mint, raspberries, rhubarb, tomatoes and lesser known herbs.
With the leaves now falling from the trees, some plants will be starting their winter dormancy in a few weeks. Strawberries are one of these plants. This means that it is an excellent time to plant strawberry runners.
Runners or seeds?
Strawberry plants can be grown from either seeds or runners.
Growing from seed is time consuming, as the plant can take up to 2 years to fruit. The seed is small, fiddly to handle and germinate and can be hard to find.
However, for those who like a challenge, after chilling the seed for 2-4 weeks in a closed container in the freezer, plant the seed in a good seed raising mix in small punnets or containers. Sieve some of the seed raising mix over them to lightly cover, and then keep moist. Seedlings can take up to 2 months to appear. Transplant to a larger pot when around 3 leaves have formed.
The seed is usually started in Spring or Autumn. The easiest strawberry to grow from seed is the tiny Alpine strawberry and its seed is available from many suppliers.
I have also heard of people picking the seed off the outside of strawberries with a toothpick and attempting to sprout plants from this seed. However, I have no experience with this method.
The alternative way of growing strawberry plants is from runners or established plants (which have themselves been started from runners). A ‘runner’ is a long shoot sent out from the original strawberry plant, which can itself establish a new plant once it touches the ground.
Runners are available from around mid-May onwards and should be purchased as ‘virus free’ to prevent receiving a diseased plant. Runners have little or no leaves and consist of a ‘crown’ and root system. They are the strawberry plants’ dormant stage.
Select runners which are moist, as this is an indication that they have been properly stored in a cool room before sale. Runners with dry roots may not establish. Plant as soon as possible after you purchase them, keeping moist until you do. Watch out for the formation of a grey, furry mould – wash off if some of this forms or, if badly affected, discard the runner and start afresh.
Plant the runner with the roots under the soil level and the crown sitting on top of the soil. Do not double back the roots when planting – if they are too long, simply trim to around 10 cm.
The most popular way to plant the runners is in zig-zag shaped rows about 30-35cm apart.
Soil preparation and aspect
If planting in the garden, prepare the soil as you would for a normal veggie patch – friable, with compost, manure, lime, etc. However, avoid putting fertiliser directly into the hole in which you plant the strawberries – too much nitrogen can produce huge leaf growth and not much fruit. Mulch with straw to keep dirt off plants and moisture in.
Strawberries can also be planted in pots or hanging baskets, in which case a good quality potting mix can be used. Liquid fertilise every month or so.
Plant in full sun if possible, however some shade will be tolerated.
Pest and disease management
Slugs, birds, lizards and all manner of critters enjoy eating strawberries. This can be a constant battle. Netting will prevent birds, as will growing in hanging baskets or containers on walls where birds cannot easily perch. Nets will also deter possums. Birds can be tricked by growing the white strawberry (more about coloured strawberries below), so they don’t know it’s ripe. Use your favourite method of slug prevention.
Strawberry flowers appear on plants around September/October and plants will fruit from November onwards, continuing into March.
After plants have finished fruiting, you can cut them back to around 10cm – re-planting any runners if more plants are desired. Every 3-4 years, consider replacing your plants to prevent virus build-up and plant in a new bed.
Strawberries come large or small, in different colours (white, pink, red), and with different flavours.
The Alpine strawberries are the smallest. Red Gauntlet and Tioga are some older, reliable, commercial varieties, of which Tioga is sweeter and Red Gauntlet less flavoursome.
Sweetheart produces a heavy crop with small, sweet fruit.
The Albion strawberry is a more recent variety which is day neutral – that is, flower buds commence with less regard to day length than for other varieties. This enables more continuous fruit production. The Albion strawberry has a very sweet flavour, so is ideal for desserts.
And finally … how many plants?
One plant is will not provide a family feast – I would try at least 10 plants and some people recommend 30. Of course, this depends how often you like eating them!