Who knew you could sow strawberries and get fruit the first year! Photo: allmanhall.co.uk & walmart.ca
Growing strawberries (Fragaria × ananassa or F. × rosea) by seed is probably not a project for a novice gardener. Young plants tiny are very delicate and germination is not always that great. And you will need a grow light. If you’re just getting started with growing plants from seed, it’s better to practice with easier varieties, such as tomatoes or marigolds, first. But when you do get the hang of producing plants that way, growing your own strawberries from seed can be a nice little challenge … and costs far, far less than buying plants!
If you want to plant strawberries for harvest the first spring, you have to start them early. Really early. Between December and the end of January, if possible, at least in the Northern Hemisphere.
Sow the seeds in a pot of moist potting soil, just pressing them into the potting soil without covering them. Now seal the jar inside a plastic bag or dome and place it in the fridge.
After one month in the cold, take the container out of the refrigerator and expose it to light and moderate heat: about 60 to 75?F (16 to 24?C). Germination is slow, usually 3 to 6 weeks, and also irregular, so always sow more seeds than the number of plants you really need, as not all will sprout.
When the seeds do germinate, place the young plants under a fluorescent or LED grow light rather than just in natural light. This isn’t really optional, because on a windowsill in midwinter, the days are short and too gray to stimulate adequate growth. It’s not before the spring equinox (around March 20) that days are long enough for you to really consider growing strawberries in natural light only. And you do need to keep the plants growing fairly quickly if you want a first-year harvest! Under a lamp, you can offer a 14 to 16-hour days that will encourage the young plants to grow their very fastest.
Place the seedlings about 3 to 4 inches (8 to 10 cm) from the lamp, raising it as the plants grow.
Ideally, you’d also keep the seedlings rather cool at this stage of their growth: 58 to 65 °F (15–18°C): this results in denser, more compact plants.
When the seedlings begin to produce their first true leaves, it’s time to remove the plastic bag and thus ensure better ventilation. From this point on, you’ll also need to start watering as soon as the soil begins to dry out. To this end, it is often easier to soak the seedling pot in a tray of water (discarding any excess water after half an hour) than to pour water over the surface of the potting soil with a watering can, otherwise the force of the flow can disturb the soil, digging up or burying the still fragile seedlings.
Transplant the plantlets into individual 4-inch (10 cm) pots about when the third true leaf appears. Do so carefully, with the crown of the plant flush with the soil. You don’t want to bury the crown to any depth.
Fairly early in the season, in early May in most climates, while the nights are still cool, start acclimatizing the young plants to outdoor conditions: a few days in the shade, then a few days in partial shade before placing them in full sun.
Finally, transplant the plantlets into the garden (or into a container) when there is no more risk of frost. True enough, strawberries can tolerate frost, but … why stress them unnecessarily just where you’ve almost reached your goal?
Strawberries prefer full sun. They’ll tolerate partial shade, but won’t be as productive. The soil should be rich and well-drained. Don’t hesitate to incorporate plenty of compost into it when you plant. Surround the plants with mulch, but without covering the leaves. Mulch will reduce weeds and help maintain a more even soil humidity. It even reduces slug damage to the berries.
For most varieties, a spacing of 18 to 24 inches (45 to 60 cm) will be adequate. Strawberry plants will produce runners (creeping stems) carrying baby strawberry plants and these will quickly fill in any empty space.
By the time this is happening, though, your strawberry plants will be starting to bloom and the first fruits quickly follow the flowers. Yum yum!
Later Sowing, Later Fruiting
If you are more patient, you can also sow strawberries in March or April, even May, and then won’t need a grow light, but then the first harvest will probably take place only the 2nd year. Sometimes, though, late-sown everbearing strawberries will produce at least a modest harvest in late summer or fall of the first year.
Three Years, Then Repeat
Strawberries are perennial and are very hardy, usually to hardiness zone 3, and therefore come back from year to year. However, they produce best during their first three years. So, at the end of the third year, pull them out and start new seedlings from December to the end of January to ensure another three years of abundant harvest.
Where to Find Seeds?
Most vegetable seed catalogs seem to offer strawberry seeds. A quick search on Google should give you plenty of sources.
Best of luck with your home-sown strawberries