How to Sow Seeds

Sowing seeds is so easy but many beginners overthink it or worry that there is a certain skill that they need and do not have. We wanted to share some information to help you understand some common terms and give you confidence to have a go. 

Seed sowing is so satisfying when you start to see little sprouts and you will soon fall in love with your little plant babies and want to protect and nurture them!

Germination

Germination simply means sprouting. Your little seedling is beginning to emerge from its seed shell. You will often see references to germination time which just means the number of days or weeks that you can expect to wait before you see signs of little seedlings emerging. 

If you read that germination can be slow or erratic then it means that the seedlings may not appear for a while and they may not all appear at the same time! Simple as that!

Temperature

Whilst there will always be exceptions to any rule, most seeds will germinate or sprout if they are sown at around 18 degrees c. If you are unsure then just go with room temperature to be safe. If you want to grow anything really exotic, we would suggest it being quite a bit warmer – around 25 degrees c. For most vegetables that you would grow in the UK then around 18 degrees c should be absolutely fine. 

Soil temperature

Try and avoid sowing seeds in really cold soil. If you are sowing seeds in the winter you should try and warm up the soil first. Try storing the soil in the house or garage for a day or two. Cold soil is only going to delay seed germination. Bottom heat will sometimes be used to encourage growth – if you sow chillies or tomatoes in January/February time this can be helpful to get them started. Keeping your seedling pots by a radiator can help with this.

Water

Seeds need water but not too much…too much can cause your seeds to rot or cause fungus to develop. We also recommend using tap water rather than rain water for seedlings. Pathogens could be present in the collected rain water.

Ventilation

Seedlings need ventilation. If air cannot circulate then fungus can form or the seedlings can develop damping off disease. We often use mini propagators which have adjustable air vents. These allow air to circulate but which also help to maintain the temperature.

Seed Depth

As a general rule, only sow as deep as the seed is thick. For the tiniest seeds, surface sowing is often the best method. This is exactly as you think, sow on the surface and do not cover them with soil. The smaller the seed, the more careful you have to be when watering. To prevent small seeds washing away you could water from below. This means putting your seed pot into a tray of water and allowing the water to soak into the soil from the bottom. 

I don’t have a greenhouse – what can I use?

A greenhouse is really not necessary for sowing seeds. A warm, bright window ledge will work just fine but try and avoid direct sunlight. You could use a clear plastic storage box as a make shift greenhouse! You can also buy window ledge propagators. By sowing seeds undercover you help to control and maintain temperature.

Pricking out

When your seedlings emerge they will emerge with their seed leaves – these are a different shape to their real or ‘true’ leaves which will follow. When the true leaves appear and the seedlings are big enough to handle you can start to prick out your seedlings to put into individual or larger pots to grow on. The seedlings are still very delicate at this stage so we often use a seedling widget, or a pencil, to gently ease the seedling from the soil without causing damage. You should always handle the seedling by the leaves and not the stem.

Damping off disease

This is a fungus in the soil which, if it develops can cause your precious seedlings to collapse and die. It is common in the spring when light levels are lower and when seedlings are sown under cover. You can help prevent this by allowing ventilation to your seedlings, by not sowing your seedlings too thickly 

Hardening off

When your seedlings have developed into strong little plants and they are ready to plant out you want to make sure they are hardened off. If you place young plants that have been grown in a lovely warm protected environment straight out into the ground this is a significant change in conditions which your little plant may not be able to deal with and it can go into shock. A stressed plant can have stunted growth or could even die.

Hardening off means that you are acclimatising your plants to their new environment gradually – by placing your plants outside each day for a few days and bringing them inside again at night when the temperatures drop they will start to get used to temperature fluctuations and will be better able to cope with their new growing environment when you plant them out permanently. 

Labelling

Make sure you always label your seeds….trust me as much as you think you will remember what you planted, you will not! 

We hope this article helps you understand some of the terms used when sowing seeds and gives you confidence to have a go. If we have missed anything or if you have any other questions please reach out to us at hello@heritageorganicseeds.com

Happy Sowing!