If you’re doubtful about when to start growing tomatoes in a polytunnel, you can do it either in autumn or early spring. This way, you can get a late yield or an initial yield depending on what you need. Another common practice is to plant in a two-crop rotation where you sow for an autumn crop and another one for a spring crop for an extended growing season.
According to the University of California, you can get up to 20 pounds per plant in a spring crop from March to June. On the other hand, you’ll get half the amount of this yield in an autumn crop from October to January. And since you’re using a polytunnel, you can plant tomatoes year-round without frost being a concern.
Knowing When To Start Growing Tomatoes In Polytunnel
Autumn, spring or a two-crop rotation for an extended growing season are the ideal times for planting tomatoes in the polytunnel. However, it’s also essential to learn the season and temperatures and use an unheated polytunnel for growing tomatoes. This way, you can correctly plant your vegetables without the risk of any drawbacks.
Seasons and temperatures
The ideal temperatures for growing tomatoes in a polytunnel are 70 to 80°F during the day and 60 to 65°F for the nighttime. Keeping this in mind, you must maintain the polytunnel’s recommended conditions when you plant either in autumn, spring, or both. As mentioned previously, you can get up to 20 pounds of yield per tomato plant when you plant spring and then half of it for autumn.
So if you’re using a polytunnel for commercial use, you can grow a spring crop from March to June or an autumn crop from October to January as recommended by UC Davis. If you want to extend your growing season, you can also plant in a two-crop rotation. Sow seeds in early June or early July for an autumn crop and seed in December to mid-January for a spring crop.
However, it would be best to remember that tomatoes will only successfully grow and produce fruit if you meet their conditions. Therefore, always check the temperatures of the polytunnel accordingly. But what about the danger of frost?
During spring, where the frost has passed, is a typical time to plant tomatoes in most areas. But if you’re in a county like Northumberland with short growing seasons and high altitude, the University of Idaho Extension recommends another time for growing tomatoes. Plant the crops before the last frost date to help extend the growing season.
Growing tomatoes in an unheated polytunnel
The temperature differences in a heated and unheated polytunnel have effects on the crops. With this in mind, you might be curious if you can still grow tomatoes in an unheated polytunnel if you live in a cold region of the UK. The good news is that an unheated polytunnel is still usable as long as you do careful planning.
Since you can’t provide heat, you can only grow tomatoes in an unheated polytunnel after the last frost date has passed. This practice will put you ahead of your planting schedule, but you’ll also be extending your growing season. Some farmers recommend sowing six weeks indoors before the expected frost date so your seedlings will be healthy enough for transplanting.
How To Grow Tomatoes Year-Round
The most significant advantage of growing tomatoes in a polytunnel is that it extends the growing season. Therefore, growing vegetables year-round is possible in a polytunnel, given that you can provide the optimal conditions for the plants. Tomatoes will fruit best from the warmth of spring and summer, but controlling the climate and using proper cultivars will let you produce fruits throughout the year.
The best trick for the year-round growing of tomatoes is choosing cultivars suitable for the current conditions. You can start the growing season early by using cold-tolerant varieties and use other cultivars for the summer. Learn more about indeterminate and determinate types of tomatoes as well.
The success of a year-round productive polytunnel will then depend on how you control the environment for the tomatoes. The Agricultural Extension Service of the University of Tennessee emphasises maintaining the polytunnel using heating, ventilation, and air distribution systems. Check the temperature, carbon dioxide, and humidity of the polytunnel year-round.
The beauty of using a polytunnel is that it’s possible to extend the growing season and even have tomatoes year-round. But do you know when to start growing tomatoes in the polytunnel? You can have a two-crop rotation for autumn and spring, but you can also grow in autumn or early spring.
If you do a spring crop from March to June, you can yield up to 20 pounds per plant. On the contrary, an autumn crop will yield 10 pounds per plant. And if you live in a short-season region of the UK, you can avoid the dangers of frost by planting tomatoes before the last frost date.
Overall, using a polytunnel is an excellent way to have a productive tomato UK garden. However, success relies on your ability and consistency in maintaining the ideal conditions for the plants. Know the proper timing and practices, and you shouldn’t feel intimidated by growing tomatoes in a polytunnel.