Pricking out tomatoes: Here's how to do it right

Pricking out tomatoes is important if you want healthy, vigorously growing plants and a good harvest. Here you will find out everything you need to know about pricking out.

Sowing tomatoes

Homegrown tomatoes have many advantages: There are significantly more different tomato seeds available in specialist stores than there are young plants of different types. In addition, the seeds cost less than young plants and you have the experience of sowing.

If you want to sow and grow tomatoes, pricking out the plants is particularly important. You can sow tomatoes either broadly in seed trays or individually in multi-pot pallets. Which solution is better for you depends on how much space you have available.

Pricking out tomatoes: What is it?

After sowing, the young tomato plants initially grow very close together in the soil. If they were allowed to continue to grow like this, they would soon get in each other's way. It is therefore important to separate the seedlings. This means placing each of the tomato plants in an individual small pot. There the plants can develop well and form a solid root ball until they are finally planted out.

Moving the tomato plants into individual pots, i.e. separating the plants, is called pricking out. As you move the tomatoes, you can weed out weak specimens. Also remove seedlings that are too long, brittle or bent over. These would not develop into healthy and vigorous tomato plants.

If you have sown your tomatoes in multi-pot pallets, you don't have to prick them out. The plants then remain in the pot until they are planted out. For this form of sowing, however, you need a lot of space on the windowsill or propagation house.

The right pots and suitable soil

For pricking out the tomatoes, get some gardening gloves and a seed dibber, both of which you can obtain from specialist retailers. If you don't have a seed dibber to hand, slightly sharpen a wooden stick with a knife. You can use the piece of wood as a seed dibber. Or you can use a crayon.

Use nutrient-poor seed or herb soil for the tomato plants. This is important because the sparse nutrients in the substrate encourage the plants to form a lot of roots. In order to provide themselves with all they need, they have to branch out their roots a lot. This will benefit the tomatoes later when they are fully grown.

Use pots that are about 10cm in diameter. The tomato plants are well taken care of there for the time being.

The right time to prick out

Take a good look at your young tomatoes. As soon as the first real leaves form on the plants after the cotyledons, space usually becomes quite tight in the planting bowl. Then you should prick out the plants. This point is usually reached about three weeks after sowing.

How do you prick out tomatoes?

Fill the pots for your young plants with seed or herb soil. Use the seed dibber to press a hole several centimeters deep. It should be deep enough for the seedlings to fit all the way in without being bent. Twist the seed dibber as you remove it from the soil. This keeps the hole narrow.

Water the seedlings in the old planter again. Then carefully grab a single one and gently lever it out of the ground with the dibber. Do this carefully so that the roots don't tear.

In the new pot, place the seedlings significantly deeper in the soil than they were previously. Insert them into the pre-drilled planting hole up to the base of the cotyledons. The plants remain particularly stable and also develop additional roots on the stem. These are also called adventitious roots.

Gently press the seedlings into their new pots with your fingers. This gives them good contact with the earth. If the seedling is very long, you can use a trick to press the soil closer to it, even deep down: Insert the dibber into the pot just next to the plant. The soil is also moved further down towards the seedling.

Care for tomatoes after pricking out

The best place for the pricked out tomatoes is a bright and protected place. This can be in the house or in the greenhouse. The place should not be in full sunlight initially. If the tomatoes go on to grow well, are healthy and strong, they can absorb enough water. They can then also be placed in the sun. Until then, you can provide shade if necessary to protect the water in the pot from evaporating.

Always keep the soil slightly moist, but not wet. At the very beginning, water very carefully using a very finely dosed nozzle on the watering can. A jet of water that is too strong could wash round the seedlings too much.

If the tomato plants soon grow larger and stronger, you can water them with a normal watering can or a garden hose connected to the rainwater barrel. Rainwater is particularly worthwhile because it costs nothing. With a battery-powered rainwater pump like the GardenPump 18 from Bosch, you can easily pump it from the barrel or cistern through the hose to the plants.

Always water the tomatoes from below. The leaves should remain dry. This way you reduce the risk of fungal diseases. You can get more tips on watering, which water is suitable and how to water your garden here.

Before you plant the tomatoes outdoors in mid-May, harden the tomatoes up. Initially place the plants in a shady spot outdoors three to four days a week. In this way they get used to the changed conditions in the fresh air.

Then plant the tomatoes horizontally in the bed. Just bend the top leaf up slightly and support it with soil. In this way, the tomato forms many more adventitious roots.

To protect your tomatoes from wind and weather, a tomato house is the ideal place.

Planting tomatoes in planters

Be sure to follow crop rotation when planting tomatoes. Tomatoes should not be planted in a bed where tomatoes were already grown in the previous year. They can't find enough nutrients in it.

If you only have limited space in the garden, simply use planters with drainage holes. A covered place is ideal for this. You can replace the soil year after year. This is important so that fungal spores from brown rot and late blight do not infect the plants. Plant about two to three tomato plants in each pot and fertilize them with a tomato fertilizer according to the manufacturer's instructions. Then before long you will get a bountiful harvest.

Tip: Do you want even more edible things in the garden and on the balcony? We also have lots of ideas for avocados, pineapplesor a herb box on the railing. 

If you want to know more about when you should do what kind of work in the garden, you can find out the best times for all the important tasks in our Gardening Calendar.