10 Tips For Cultivating Tomatoes

Whether outdoors, in a greenhouse or on the balcony: A warm place, the correct choice of variety and appropriate watering and fertilizing are decisive for a rich tomato harvest.

Apr 09, 2021 02:20 pm
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Fresh tomatoes

Harvesting the fruit of the tomato plant’s labor is an almost indescribable pleasure

Table of Contents

The tomato is by far the most popular vegetable among hobby gardeners and even those with only a small balcony space available cultivate special tomato varieties in pots. Despite all the cultivation habits, there are numerous tips and tricks for promoting the taste and resilience of this popular fruit vegetable. Here are the most important ones.

1. Choose Resistant Varieties

The dreaded blight (Phytophthora infestans) is becoming a more and more common occurrence in tomatoes. The fungal spores are spread by the wind and rain. Previously, there was only one type in Germany, but now, several, much more aggressive forms have developed. Even varieties that are considered resistant or tomatoes grown under protective cover are not fully immune, although often only older leaves are affected, the fruit generally remains healthy and the plant grows bravely on. Breeds for eco-cultivation, such as ‘Dorenia’ or ‘Quadro’ have also shown that they can deliver a reliable harvest and excellent fruit quality, even in less favorable conditions and the most varied locations.

2. Cultivation Under Glass And Film

With a small greenhouse, film tunnel or tomato house, you can bring forward planting and harvesting by up to four weeks. Unlike in a flower bed, regularly changing the fruit for space reasons is difficult, this means soil pests such as lesion nematodes and Pyrenochaeta pathogens can spread easily.

Tomato greenhouse
Cultivating tomatoes in a greenhouse has its own very unique charm

Dense growing breeds grafted to robust wild tomatoes are extremely resistant and yield more than ungrafted tomato plants, particularly in cooler weather.

3. A Healthy Little Fruit

Tomatoes contain 13 vitamins, 17 minerals and lots of secondary plant materials. The red dye lycopene from the group of carotenoids is considered particularly valuable and not only protects against sunburn, but can also help to prevent circulatory diseases, inflammations, and cancer. The content is determined by the maturity and also the method of cultivation. Scientists discovered that ecological tomatoes that were only sparsely fertilized contained more of these cell-protecting antioxidants than conventionally cultivated fruit. The newer breeds such as ‘Licobello’ or ‘Prolyco’ are particularly rich in lycopene and other carotenoids.

4. Planting And Fertilizing Tomatoes

Even robust early varieties such as ‘Matina’ should not be brought outdoors before the middle of May. If you plant tomatoes 1.97 to 3.94 inches deeper than they stood in the pot, they will form additional roots around the stem base, become more sturdy, and be able to absorb more water and nutrients. Moreover, a planting distance of at least 23.62 inches ensures that the fruit receives enough light and air. Adding compost when preparing the plant bed is a sufficient initial fertilizer. The plants require supplementary nutrients every two to three weeks after the flowers begin to form, for example from a potash-rich tomato or vegetable fertilizer.

Planting tomatoes
It is important to take distances and depth into consideration when planting
5. Bush Tomatoes For The Balcony

Low-growth bush tomatoes with an overhanging growth shape are ideal for cultivating in window boxes or hanging baskets.

Hanging tomatoes

Use this growth shape to put your tomatoes in center stage

In contrast to stake tomatoes, varieties such as ‘Tumbling Tom Red’ are grown with several shoots and there is no need to remove shoots from the leaf axils. In order to ensure they develop lots of panicles on which new flowers and fruit continuously mature until the fall, despite the limited root space, plant them in high-quality balcony potting soil or special tomato soil and add a low dosage of liquid fertilizer to their water every week. Excess nutrients will cause the leaves to roll up!

By the way: If you have robust bush tomatoes that thrive in pots and are still healthy in the fall it is worthwhile trying to overwinter the tomatoes.

6. Green Tomatoes - Pleasure Or Poison?

Unripe tomatoes that are still green contain poisonous solanine and should not be eaten, or only eaten in very small amounts. One to two medium-sized fruits contain approx. 0.0009 ounces of the bitter substance. This does not break down, even when heated. Sensitive subjects react with headaches and digestive problems such as nausea. The fruit of tomato breeds such as ‘Green Zebra’ or ‘Green Grape’ remain green or striped yellow-green even when fully ripe. The later these are harvested, the less solanine they contain. The fruit is best picked as soon as the flesh gives slightly when pressed gently. This is when the bitter substances have broken down and the tomatoes taste refreshingly acidic.

Green tomatoes
"Green Zebra"
7. Tying Up And Removing Epicormic Shoots From Stake Tomatoes

Most tomato varieties are grown on a single shoot. Ensure the stem does not bend under the weight of the fruit by tying the plant to a bamboo, wood or spiral rod made from aluminum or stainless steel. Break off the side shoots in the leaf axils (‘epicormic shoots’) as soon as you can get a good grip on them with your finger tips. If you simply leave them to grow, a large amount of the fruit will mature late. There is a risk of fungal infection as the dense foliage only allows rain or dew to dry off slowly. Regularly pruning tomatoes also ensures that you can harvest more aromatic fruit and that your plants remain healthy.

8. Harvesting Aromatic Fruit

Tomatoes in the greenhouse ripen between the end of June and November. Outdoors, you will have to wait until July and the harvest is finished by October at the latest.

Juicy tomatoes

The most aromatic fruit is found in the shade of the leaves

Aromatic fruit does not thrive at a fast pace in the blazing sunshine, rather it matures slowly in light foliage shade. Refrain from removing shoot leaves around the fruit, as used to be common practice, and also from the frequently recommended plant tip removal. Only remove leaves until the first fruits form to avoid fungal infection. Then prune the inflorescences on the shoot tips in the late summer, as their fruit will no longer mature in the fall anyway.

9. Ensure The Quality Of Younger Plants

Ensure tomato plants that are bought pre-cultivated have a stable root ball, spot-free, completely green leaves and a strong stem with short distances between the leaf bases and panicles. These criteria also apply if you grow your own saplings. You should sow from the middle of March at the earliest, otherwise the plants will soon hassle one another on the window ledge, but nonetheless continue to grow too tall due to the extremely low provision of light, and form fewer flowers and fruit.

10. Shake For Plentiful Fruit Growth
Tomato flowers
Shaking helps nature along a little here

If you grow tomatoes in a greenhouse, leave the window open during the day to ensure bees and can pollinate the flowers. The pollen sits tightly packed in porous capsules on nightshades such as the tomato. You can shake the plant repeatedly to ensure that it releases its pollen. Outdoors, the wind does this job for you. However, at temperatures over 86 degrees Fahrenheit or in high humidity, the pollen sticks and even shaking will not help here.