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Get off to a good start with your tomatoes in March
Not long until the first tomato seeds can be put into the ground. At TagTomat, we are quite crazy about tomatoes, as the name implies. We are ready to get started with the pre-germination process and cannot wait until March. We are especially excited about this year because we went all in and got 23 new tomato sorts, which we are very excited to share with you. Until then, here is a step-by-step guide on how we pre-germinate our tomatoes.
Guide: the pre-germination of tomato seeds
Pre-germinate your seeds indoors in little pots from around mid-February to mid-April. Our experience tells us, that it pays off to wait with the pre-germination process until the beginning/the middle of March, if the tomatoes are planted in the greenhouse later, and until mid-March, if the tomatoes are planted outside of the greenhouse. At that point, the days are a little longer and brighter, and your tomatoes will not get lanky. But we get why it is hard to wait, we sometimes put some seeds in the ground a little too early as well. But the seeds we plant a little later always overtake the ones planted early. It is therefore better to pre-germinate for example chilli, pepper, and aubergine in February.
(1)
Fil your pots/seed tray with potting soil and water the soil so it becomes moist but not too wet. It is important to make a hole in the bottom of your pots, so that excess water can drain off, making sure the seeds and future tomato plants don’t rot.
(2)
Place one or two seeds in each pot and cover with 0.5 cm potting soil and water the top layer with a sprayer.
(3)
Place the pots in a warm place – optimally around 22-27 °C. For example, place them over a radiator or on a warm floor. Wait round 4-10 days and your seeds should start to germinate. Pay attention to the soil, so it doesn’t dry out. You might put a lid on top, to keep in the moisture or keep the soil moist with a sprayer.
(4)
Pay attention to when your seeds have germinated. When the seeds have germinated, place them in a bright window, and remove any lid. When pre-germinating before March, it is wise to use a growth light, otherwise the plants might turn lanky.
(5)
Make sure the soil doesn’t dry out but avoid over watering. Tomato plants are happy for nutrition, so make sure to continuously fertilize your tomato plants, when the first permanent leaves have developed.
(6)
If you have planted more than one seed in the same pot, either remove the smallest plant or replant it in a separate pot, when they have the first set of leaves. This is also the time when your plants are ready for bigger pots, if you have planted them in small seed trays. Be careful when replanting and plant to regular nutrient potting soil. Make sure to water when replanting.
(7)
Repot continuously as necessary. When the roots are starting to show in the bottom of the pots, the plants need more soil. Make sure not to repot into a much larger pot, instead continuously go a pot size up.
Enjoy the pre-germination process!
Team TagTomat

Om TagTomat
Behind the Danish company TagTomat (in English ‘Roof Tomato’) is a skilled team whose passion is to create green communities and inspire to green do-it-yourself and do-it-together projects. Today TagTomat sells organic flower seeds and vegetable seeds, which are packaged with our seed packaging machines from 1895. It all began in 2011 in the heart of the neighbourhood Nørrebro in Copenhagen with just five self-watering plant boxes on a wheelie bin storage. You can read more about TagTomat at our website TagTomat.
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