Sowing and pre-cultivating tomatoes

If you would like to sow and pre-cultivate tomatoes, you’ll need to pay attention to a few important points. You can find out how to successfully cultivate this fruit using our guide.

Apr 09, 2021 02:22 pm
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Sowing tomatoes
If you want to cultivate something beyond the standard varieties you should sow your own tomato plants

Sowing and pre-cultivating tomatoes provides hobby gardeners with lots of benefits. If you buy young tomato plants in a garden center or even at a weekly market, you’ll save yourself the effort of sowing, but you will also have to make do with a limited variety. Sowing yourself is fun and saves cash, as tomatoes are much more valuable as ready-grown young plants. Order or buy seeds as soon as possible in February or at the start of March, as new and rare old varieties typically sell out quickly. You can pre-cultivate open pollination varieties from seeds you have harvested yourself.

Sowing and pre-cultivating tomatoes: Everything you need to know at a glance

Tomato sowing is recommended at the end of February at the earliest. If you would like to pre-cultivate tomatoes on the window ledge, then the perfect time for this is the start/middle of March. Sow the tomatoes in bowls, small pots or seed trays with potting soil. Lightly cover the seeds with soil, place a film or transparent cover over the top and keep the substrate evenly moist. A bright place with a moderate ambient temperature is important, otherwise etiolation will occur in the young plants. The tomatoes will germinate after about ten days at a temperature of between 64.4 and 77 degrees Fahrenheit.

When should I sow tomatoes?

We do not recommend sowing the tomatoes before the end of February, as tomatoes require lots of light and are quickly prone to etiolation with a lack of light. They form long, brittle stems with small, light-green leaves. When pre-cultivating them on a window ledge, you should even wait until the start/middle of March. It’s best to use a seed tray with a transparent lid. Fill this with potting soil from a trade center. Alternatively, you can also sow the seed kernels in small pots or seed trays, it is then much easier to prick out (separate) the individual saplings later on, or you may not have to prick them out at all. As the seeds do not need light to germinate, you should cover them with around 0.02 inches of soil after sowing, water thoroughly and keep evenly moist. This work can be done particularly easily on a planting table.

Sowing tomatoes: Step-by-step guide
Filling plant pots with soil
Photo:MSG/Folkert Siemens
Filling plant pots with soil
Filling plant pots with soil
Photo:MSG/Folkert Siemens
01
Filling plant pots with soil

Fill the planting container before sowing - here is a variant made from compressed turf - with low-nutrient sowing soil.

Sowing tomatoes
Photo:MSG/Folkert Siemens
Sowing tomatoes individually
Sowing tomatoes
Photo:MSG/Folkert Siemens
02
Sowing tomatoes individually

Tomato seeds germinate very reliably, so they should be placed individually in planting pots. Then lightly sift soil over the seeds.

Moisten the sowing soil carefully
Photo:MSG/Folkert Siemens
Moistening the soil
Moisten the sowing soil carefully
Photo:MSG/Folkert Siemens
03
Moistening the soil

Keep the substrate evenly moist after planting the seeds. A spray bottle is ideal for moistening, as a watering can would easily wash away the fine seeds.

Tomato seeds in a mini-greenhouse
Photo:MSG/Folkert Siemens
Cover the
Tomato seeds in a mini-greenhouse
Photo:MSG/Folkert Siemens
04
Cover the

A humid climate develops in the mini greenhouse under the transparent hood; this quickly promotes tomato germination.

How should I care for tomatoes after planting out?

Open the cover every day to refresh the air. It takes about ten days until the first seed leaves are visible at a germination temperature of between 64.4 and 77 degrees Fahrenheit. The young plants must be pricked out as soon as the first proper leaves have formed. Use a special pricking out tool for this, or simple the handle of a cutlery spoon. Use this to carefully lift the roots and then place the tomato plant in a new pot (flower pot with a 3.54 inch diameter) with normal potting soil. If you have sown the tomatoes in a seed tray, simply place them and their entire root ball in larger pots.

Continuing to cultivate tomatoes after pricking out

Initially, continue cultivating the tomatoes on the window ledge or in the greenhouse until they reach approximately 11.81 inches tall. Take care to ensure that the ambient temperature after they have begun growing is not too high - 64.4 to 68 degrees Fahrenheit is ideal. At higher temperatures, for example over a radiator on the window ledge, the young tomatoes will grow shoots rapidly, but they will not have enough light for this growth pace.

When should plants which have been brought on be planted out?

After the last frosts (middle of may), you can place the young plants in the plant bed. However, tomato plants are healthier and yield more fruit if you keep them in a greenhouse or protect them from rain in a tomato house. Fertilize the plants for the first time after then have been in the bed for about a week.