Strawberry Requirements
No matter when you’re growing strawberries, you must meet their basic needs. These perennials like loose, fertile, well-drained soil. The pH should be 5.5 to 6.0. Regular water means healthier plants and more berries, but too much increases the risk of rot. Fertilize when the plants first start to grow after dormancy and monthly thereafter until berries start to develop. Use commercial 10-10-10 fertilizer or make your own.
New Varieties
June-bearing strawberries are the classic one-large-crop varieties. In the Northern hemisphere, they usually bear in late May or early June – hence the name. Over the years, breeders have refined these to produce with less light. Known as short-day strawberries, these plants will bear in warmer climates like Florida and California during the short days of winter.
Short-Day Varieties
Strawberries that produce blooms and fruit with less than 14 hours of daylight are considered short-day varieties. They will also produce in cooler temperatures. These are short-day varieties:
- Allstar
- Benicia
- Chandler
- Earliglow
- Florida Radiance
- Gaviota
- Honeoye
- Jewel
- Mojave
- Surecrop
- Tillamook
- Totem.
Greenhouse Growing
If you live in a colder climate, it’s still possible to grow strawberries in winter. An insulated greenhouse offers the right environment. Short-day varieties planted in the greenhouse will ripen fruit successfully. You may need a heat source in really cold areas. In Victorian times, growers placed piping throughout the greenhouse and ran hot water from wood-fired boilers through the pipes. You can also use heat mats.
Growing Under Lights
If the only place you have to grow strawberries in winter is the basement, that’s still doable. Everbearing strawberries may be the best choice, as they are bred to produce successive crops, although both berries and the total crop are smaller. You’ll need full-spectrum lights that include all the colors found in natural sunlight; keep them on 14 hours a day.
Imported Strawberries
If you find strawberries in the grocery store at Christmas time, the odds are high they’ve been imported. Mexico is a common source of winter strawberries for the US. Since the seasons are reversed, winter strawberries also come from South America. However, the warmer regions of both California and Florida can grow winter strawberries as well, with Florida leading in domestic production.