Growing strawberries in your garden can be fun and rewarding. However, the crops are generally sensitive to cold and produce fruit only through a short and comparatively warm season. If you’ve got a greenhouse, you can protect your plants from chilly days and expand the strawberry harvest. Picking the best varieties for greenhouse growing is the first step in ensuring a permanent and successful harvest.
Traditional, antique strawberry varieties flower and set fruit in the spring or early summer, generally stopping production when days become more in late summer. But some varieties such as “Tristar” are day-neutral, setting fruit regardless of the period of daylight. Should you plant “Tristar” strawberries in trays or pots in the greenhouse in early spring, then they could produce fruit throughout the summer and under controlled greenhouse temperatures, continue to set fruit well into autumn after chilly weather arrives. “Tristar” creates particularly high yields of exceptionally sweet, delicious fruit.
The number “Selva” is just another day-neutral strawberry assortment which produces unusually large berries and grows well in a greenhouse. Like all strawberries grown indoors, “Selva” requires hand pollination when in flower to ensure fruit production. To pollinate plants, then gently pass a camel hair brush from flower to flower across several plants. As an alternative, you could present a nest of natural pollinators such as bumble bees into your greenhouse. The bees will travel from flower to flower, moving pollen as they do so.
“Albion” is a day-neutral variety that was created in the University of California. It creates strawberries having an unusually high sugar content, which makes them excellent choices as new additions to desserts. “Albion” can also be particularly resistant to several fungal diseases that can be an issue at a greenhouse where humidity will be high, including verticillum wilt, which causes leaves and flowers to fall, and several kinds of crown decay which could damage or destroy crops.
“Jewel” is a remarkably productive strawberry variety that also has fruit with strong, sweet taste. Although the number is not day-neutral, it can be successfully grown in a greenhouse, according to horticultural experts at Cornell University, who recommend using succession planting to extend the harvest. Remove outdoor-grown plants in fall, when temperatures fall, and plant some in the greenhouse, storing the others at a cool location at about 30 degrees Fahrenheit. Move classes of cold-stored plants into the greenhouse at staggered intervals, planning approximately 12 weeks from re-planting until harvest. With this plan, you can harvest fruit from “Jewel” for many months.