How To Grow Tomatoes – Which?

Tomatoes are easy to grow both indoors and in the garden. They are suitable for pots and growing bags and are therefore also perfect for terraces and balconies.

How to grow tomatoes: month after month

The best tomato variety

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How we try tomatoes

We grow many varieties side by side, harvest tomatoes regularly and count and weigh the fruits of each variety. We also try the tomatoes, evaluate them according to taste and texture.

When to sow

Indoor plants

If you sow tomatoes too early, the natural brightness will be too low and you will end up with large long-stemmed plants that will not grow well. Mid-March is ideal for tomatoes grown indoors in a greenhouse or multi-base.

Sow the seeds in a pot or container Best Buy compost to sow seedsThey need a temperature of 15-20 ° C to germinate. Therefore, place them indoors on a warm window sill or in a heated propagation. When the seedlings have come out, they can be placed in individual 7 cm pots from one Best Buy compost for growing young plantsCarefully hold the leaf – never the delicate stem – then release it from the compost by lifting it under the pencil. Then make a hole in the new compost pot and place the seedling in it so that the leaves are just above the surface of the compost. Keep them in a bright place – on a heating mat in the greenhouse or under a light in the house. Two weeks after putting them in their own pots, put them in a slightly larger pot as they grow fast. Do not feed your plants at this time.

Plants for outdoor growing

Tomatoes die from frost, so you do not want them to be ready to plant until the frost threat passes in mid-late May. Wait until early April before sowing plants outdoors. Do the same as you did for houseplants (above).

Take care of your plants


You can use it in the garden or in large pots or growing pocketIf you are using pots, fill them with a mixture of a Best Buy compost for containers and a Best fertilizer fertilizer with controlled releaseThere should be 50 cm of soil between the plants. Do not plant outdoors until the risk of frost has passed in mid or late May.

To help your plants grow, tie a string to the greenhouse ceiling and place the end under the tomato plant or place a bamboo pole next to the plant. Arrange the plants so that the soil or compost is directly under the first pair of leaves. This will encourage the plant to develop more roots to make it more stable.

Grown in a hanging basket

There are varieties that are grown densely and bushy and are perfect for growing in a hanging basket. Place the plant in a 40 cm diameter basket and place it out when the risk of frost has passed, in the middle of late May.

Learn more about growing tomatoes in a hanging basket


Most varieties should be grown as a crown, which means only on one stem. Shrub species are sometimes grown outdoors and can be left alone with a few short sticks to prevent them from falling down.

Cordon plants should be tied to their support regularly and the side shoots grow between the main stem and the leaf distance as soon as they appear. This leads the energy of the plant to produce flowers and fruits rather than the additional growth of the leaves.

to water

Tomatoes are thirsty plants, so you need to water them regularly – twice a day for container plants in warm weather. Try not to get water on the leaves as this can cause disease problems.


Diet is important to produce the sweetest tomatoes. The easiest way to feed is to add controlled release feed to the compost when it is planted in pots. If you are planting in the garden or in growth bags, add liquid tomato paste to the water after the first flowers appear.

Plants grown in pots will also benefit from late summer when the controlled release feed runs out.

Fruit ripening

To encourage the development of all the fruits, pinch off the main growth point of the plant in early to mid-August and remove any new leaves or flowers that appear. This is to conduct the plant’s energy so that the fruits can mature before returning colder in the autumn.

How and when to harvest

The harvest of: August to October

You can choose how ripe you want your tomatoes to be: semi-colored for hot, dense fruit or colored for sweeter and softer fruit.

To pick the fruit, gently lift it with your thumb on the cup (star-shaped green pieces on top of the fruit) so that it stays on the fruit after harvest. This allows you to keep the fruit longer.

Each time you pick all the fruit in a group (the fruit group), remove the leaves at the bottom to improve the air flow around the plant and make it easier not to wet the leaf when it is watered.

How green tomatoes ripen

At the end of the season, you sometimes have green tomatoes that are not ripe before the cold weather passes. Remove them from the plants before pulling them up and inserting them. You may have heard of several methods recommended for ripening green tomatoes, including putting bananas, but when Which? Garðablað With some methods we have found that it is best to put them indoors in a dark place like a drawer. Tomatoes with bananas were one of the worst ways to rot tomatoes.

Save your crop

You can freeze whole tomatoes, but it can be easier to prepare dishes such as tomato sauce or soup first. You can also cut 6 mm strips and put in a dryer – this costs about 50 pounds.

Common growth problems

Leaf scroll

Tomato leaves sometimes curl when the temperature is too high. The plants will still grow, so it is not a problem. On hot days, try to cool the greenhouse by opening the door and all the ventilation and windows.

Read more about leaf curls.


This fungal disease usually occurs in late summer and requires warm, humid weather – you can apply Epidemic clock for alerts in your area. The first marks on the stems are large dark brown spots that can spread and kill the plant. Similar spots form on the leaves, although they may be lighter or grayer. It takes very little time to cover the leaves and then they wither and die. The fruits get a reddish-brown marble color. Avoid wetting greenhouse plants as they need moisture to spread. Unfortunately, there are no treatments for this and infected plants should be removed as soon as possible. You can be in green container because erythema requires a living plant tissue to survive.

Read more about the eruption

Common fruits

The fruit can sometimes be left open, often in narrower varieties such as cherry tomatoes. You can still eat the fruit, but they can mold if left over. Irregular fluid is the root of the problem. So try to water every day. Outdoor plants are particularly sensitive as they can experience a sudden current in rainy weather.

Read more about risk growth


Sometimes the ring on top of the fruit turns green and does not mature. It usually occurs in hot weather, so improving ventilation by opening the greenhouse door and opening vents and windows will help. The fruit can still be eaten.

Read more about dollars.

The end of the flowers rots

This creates a brownish, leathery spot on the lower part of the fruit. You can still eat the unspoiled parts. It is caused by a lack of calcium due to irregular hydration and high fever. Water your plants regularly and lower the temperature by opening the greenhouse doors and all ventilation and windows.

Read more about bud rot.

Tomato grinders

This green worm nibbles on fruits and leaves. Take care at night when it is most visible and remove everything you find.

Read more about tomato grits