Is it possible to overwinter tomato plants? Here is an explanation of whether and under what conditions it makes sense to overwinter these heat-loving plants.
Can tomatoes be overwintered? The answer to this question is: as a rule, it is not useful. But there are circumstances in which overwintering in the pot and house may be possible. Here is what you need to know about it.
Can you overwinter tomato plants?
Tomatoes originate from South America, where they are cultivated perennially due to climatic conditions. In temperate climates, however, the plants grow as annuals, as they need a lot of heat and especially light to thrive. Wintering tomatoes in these areas is usually not useful, because the plants simply do not survive the cold season. They can tolerate temperatures of up to 1 °C / 34 °F for a short time, but at temperatures below 9 °C / 48 °F they will no longer grow. For good fruit to form, the thermometer must climb above 18 °C / 64 °F. The fruits get their typical red color only at temperatures above 32°C / 90 °F.
Another problem for overwintering is that most tomatoes are already too badly affected by late blight by the end of the season. This is a fungal disease that occurs mainly outdoors. In greenhouses, there is less infestation, but here other diseases can affect the tomato plants. Because the diseased plants usually do not survive the winter, it is more advisable to grow new tomato plants every year.
How is it possible to winter tomatoes?
You can test overwintering small varieties of balcony tomatoes, grown in pots and still healthy in the fall. So-called bush tomatoes are the most suitable. They grow only to a certain height, about 60 cm (24 in) high, depending on the variety, and then finish with a flower bud. Check the plant thoroughly for diseases and pests beforehand.
Where to overwinter tomatoes?
Tomatoes survive the winter on the windowsill
For trying to overwinter a robust and still healthy bush tomato plant, a bright place indoors is suitable, preferably a windowsill in front of a south-facing window. It can be helpful to improve the light conditions for the tomato with certain plant lamps. Leaving the stingy shoots on the plant, keep the soil moderately moist, but not wet, during the tomato’s overwintering. Fertilize quite sparingly and check the tomato plant regularly for pests.
Tomatoes overwinter in the greenhouse
It may also be worth trying to overwinter tomatoes in a heated greenhouse. Hardy bush tomatoes are also best suited for this. Provide temperatures between 22 and 24 °C / 72 and 75 °F during the winter months and sufficient light.