In the field, in containers or in a greenhouse - tomatoes can be grown anywhere. However, they are only optimally protected in a greenhouse. However, you can find out what you need to be aware of here.
Tomatoes are a must for many hobby gardeners in their own garden. But unfortunately they are very sensitive. Whether outdoors, in a pot or in a greenhouse - there are a few things to consider for each location so that the tomatoes thrive and are protected from diseases.
Hobby gardeners who already own a greenhouse or at least have the space to buy one can count themselves lucky. Because such a greenhouse offers a number of advantages if you want to grow tomatoes. A very important aspect here is protection from the weather. Because the summer heat, for example in combination with high humidity, can cause fungal diseases such as late blight and late blight on the plants. In the open air, the plants are usually at the mercy of the weather without any protection. In the greenhouse, on the other hand, you can influence the climate with the right equipment so that the tomatoes have the ideal conditions for good development. And as you know, he althy plants are much more resistant to pests and diseases.
Prepare the greenhouse before planting the tomatoes
➤ Make sure you have the right equipment
Not every greenhouse is ideal for growing tomatoes. Tomatoes need a lot of light, so the cladding of the greenhouse must be plastic or glass, very translucent and clean.
Tomatoes thrive best at a temperature between 20 and 30 degrees Celsius. Ideally, the greenhouse should therefore have a heating system that can keep a constant temperature. Second, it should allow ventilation to regulate the temperature.
Tip: By using such a heating system, you can extend the cultivation period and thus the harvest.
Although the tomato plants need sunlight to develop, in midsummer the sun can get so intense through the glass that it can cause sunburn on the plants. To avoid thisit makes sense to provide the greenhouse with sun protection. A shading net, for example, which is stretched over the greenhouse at the top, is suitable for this:
Tip: You can also simply install interior blinds or similar in the greenhouse.
➤ Prepare the soil for the tomatoes
Because tomatoes develop deep roots, the soil in the greenhouse should be deep. In addition, the plants need sufficient nutrients. You can upgrade the soil with compost or manure or you can apply a potassium-rich tomato fertilizer, such as the COMPO BIO long-term tomato fertilizer.
Tip: To counteract any fungal infections in advance, you can shower the soil with field horsetail broth a few days before planting the tomatoes.
➤ Equip the beds with climbing aids
If you want to use the climbing aids from the previous year, you should clean them thoroughly with washing-up liquid and hot water before use. In this way you prevent any pathogens that may still be on them from damaging your tomatoes.
There are various climbing aids for vegetables. For example, spiral rods are very suitable for tomatoes. You can also guide the tomato plants upwards on strings. In this case, it's best to set up wires beforehand that you can attach them to later.
Some tomato varieties are particularly suitable for greenhouse cultivation
If you decide to grow in a greenhouse, you should pay attention to certain varieties when you buy them. Because there are varieties that are particularly suitable for cultivation in a greenhouse. Space is a bit limited in the greenhouse, so the stake tomatoes are particularly recommended, as they tend to grow taller and are directed upwards.
Tip: If you want to obtain seeds for further cultivation yourself, then the varieties should be seed-proof, hybrids and crosses would be extremely unsuitable for this purpose.
Particularly recommended varieties for greenhouse cultivation include Tigerella, Dolcevita F1 hybrid, San Marzano tomatoes, Bernese rose, Pannovy F1 hybrid or Yellow Pearshaped. Grafted tomatoes are also robust. They are more resistant and also grow faster than the ungrafted varieties. You can buy such varieties in good gardening shops. Experienced hobby gardeners can also graft the young plants themselves. Instructions are available here.
Tips for growing tomatoes
❀ Tip 1:
ItIt is up to the gardener to decide whether to grow the tomatoes from seed or to use young plants. However, it is usually better to get young tomato plants.
❀ Tip 2:
If you have an unheated greenhouse, you will have to wait a little longer before planting because tomatoes are very sensitive to frost. To be on the safe side, you should wait until around mid-May, then the ice saints will also be over. On the other hand, if the greenhouse is heated, you can start planting around the end of March.
❀ Tip 3:
When buying, make sure you choose strong and he althy plants. If possible, you should already have a flower cluster.
❀ Tip 4:
Never plant more than three plants per square meter. This gives the plants enough space and allows them to thrive.
❀ Tip 5:
If it is very sunny in the days after planting, you should definitely protect the young plants until they are properly established. By the way, to keep soil pests away from the tomato plants, you can plant them under with marigolds or marigolds.
Caring for tomatoes in the greenhouse
➤ 1. Watering tomatoes in the greenhouse
Keep the soil nice and moist after planting. Only water the plants in the root area. Moisture on the leaves can promote fungal infections. Also make sure that there is no waterlogging.
Tip: Choose a suitable irrigation system that supplies the plants with water from below. Drip irrigation has proven itself. Since only little liquid is used, only correspondingly small amounts of water evaporate and the humidity can be kept low.
➤ 2. Avoid permanently high humidity
As mentioned above, too high humidity is not good for tomato plants because plant diseases can develop. That's why you should ventilate the greenhouse every day.
Another reason for daily airing is so that insects can get into the greenhouse and take care of the fertilization of the tomatoes.
Tip: In cooler weather, there is much less ventilation. As a result, under certain circumstances, not enough insects can get into the greenhouse for pollination. Then you should go into the greenhouse every other day late in the morning and shake the tomato flower clusters very gently.
➤ 3. Tomatoes also need climbing aids in the greenhouse
Since you're in the greenhouseWhen you have limited space, you need to make sure your tomato plants don't get in the way of each other. You should therefore provide your tomatoes with a climbing aid from a growth height of 50 centimeters. We recommend using spiral sticks like this one. These offer the advantage that the tomato plant does not have to be tied up separately, as would be the case with plant sticks. The plant finds enough support in the spirals and can thus withstand the weight of the fruit without any problems.
➤ 4. Fertilize now and then
If the color of the leaves is quite pale or the tomatoes are struggling, you should feed them with a fast-acting liquid fertilizer. Especially with tomatoes in the greenhouse, it is important that the fertilizer does not contain too much nitrogen. You always get care instructions when you buy the plants. After that, you should definitely look into it. (Reading tip: Fertilize tomatoes - That's how it's done)
➤ 5. Cut out the tomatoes
To ensure that the plants grow upright, you should remove the side shoots every week. Tomatoes are often attacked by aphids or whiteflies. You should therefore examine the undersides of the leaves at least once a week so that you can take appropriate control measures at an early stage.