It’s the time of year where you can get a head start on growing some of your favourite vegetables and flowers by sowing seeds indoors in the spring.
Outside sowing can’t start until the soil is warm, usually late April/early May so by starting warm climate crops like tomatoes indoors, you will be planting out 4-6 week old seedlings giving them more time in the short season for their fruit to ripen.
Ideally, start sowing in a seed propagator. It will give them a much better chance at survival because it acts as an incubator for your seeds. It tricks them into thinking it’s warmer than it actually is.
It’s recommended that you sow more than needed so you can select the strongest seedlings to plant out, but have some spare to replace any that don’t make it in the outdoor environment. For salad and veg it’s a good idea to sow a small amount every couple of weeks to ensure you have a supply of fresh produce throughout the summer.
To get started sowing seeds indoors, fill a tray with seedling compost. Sprinkle your seeds thinly on top of the compost or if they’re a little bigger, gently push them into the compost. Follow the instructions on the seed packet for the depth to plant them, and how far apart they should be.
Sieve compost over the seeds so they’re at the correct depth, then using a watering can with a rose head, gently water the seeds in.
Top Tip: Label the seeds with the variety and sowing date. This makes it easier to detect if there is a problem in the early stages of growth.
It’s important that the seeds are not overwatered, keep the soil a little on the dry side to encourage a more extensive root system as they search for water, and use water at room temperature to avoid stressing the emerging seedlings.
Top Tip: Use vermiculite when starting off seedlings in trays, it has moisture holding properties, if applying a liquid plant feed it will act as a nutrient store by preventing the feed washing through the potting mix.
Once the first shoots emerge the seedlings need light to photosynthesise therefore the heat/light balance in the propagator becomes important. If it’s too hot, with not enough sunlight, seedlings will grow fast to try and find the light, this results in long, spindly, weak stems.
If this is an issue, consider using a grow light. It emits the same light spectrum as sunlight and can be placed on, or suspended over, the propagator.
It’s important that the seedlings don’t freeze. The optimum germination temperature varies for each seed variety. A propagator allows the seedlings to be kept at the optimum temperature.
Keep seedlings in the propagator until they have 3-4 true leaves. They are then large enough to plant out in the garden after they have been hardened off first.
With the right tools and care, sowing early in the year is an easy and satisfying way to grow strong and healthy seedlings.
If you have a question or need any further help, please contact our team.