Why to grow from seed
Growing your own plants from seed can be both fun, rewarding and cost-effective! Raising a plant from a tiny seed to a table full of fresh produce is hugely satisfying and great for your physical and mental health. By growing from seed you control everything going into your food and there’s no worrying about mysterious pesticides that your veges may have been sprayed with.
How to grow from seed
Growing from seed for the first time can be daunting, but the only way we learn is by doing! The great news is a bag of seed is much cheaper than lots of seedlings, so even if you struggle and lose some plants along the way, ultimately you’ve got much more forgiveness financially and you can always plant again!
Though, with the right ingredients, growing from seed can be fun and easy. Here’s a beginners checklist;
Containers for growing from seed
There are so many options when it comes to containers for raising your seedlings. I often use previous seedling trays I’ve bought plants in from the season prior. These last for years and can be used over and over again. If you’re using this style of container, you will need also need a tray underneath to hold a bit of water. If you don’t have a specific plant tray available, I use my least favourite oven trays!
I also love to use my homemade self-watering seedling pots, made from upcycled soda bottles. These have the added bonus of very infrequently needing water, and being able to sustain larger plants.
If you don’t have any of those handy, use whatever you have! Leftover plastic cups or yoghurt pottles with holes poked in the bottom, toilet rolls with one end folded in – anything deeper than about 4cm, that will hold soil and moisture, and drains well will do the trick!
I do advise newbie seed starters to avoid the compostable style peat seedling pots. The reason being they are prone to drying out much faster than a typical seedling pot, as they dry on all sides simultaneously rather than just the top. This means it’s much harder for a beginner to ensure consistently moist soil and a lack of consistent moisture is one of the number one reasons for seeds failing to germinate, and seedlings failing to flourish.
When filling your containers with soil, leave 1cm or so before the rim of the container, and water well.
Soil to use
The ideal soil to start your seeds in is a dedicated seed raising mix. My favourites are Daltons and Tui, as they consistently provide a fine grain soil without large chunks and things which could obstruct a tiny sprout from reaching the surface. This will give your little seeds the best chance in life.
That is not to say that you MUST use a seed raising mix. Seeds love to grow and will do their best wherever you put them. If you’ve got potting mix or garden mix that’s great too, just try and remove any large chunks like bark which could get in the way. Some people sieve these mixes before planting to remove any chunks.
If you don’t have a garden mix any soil will do! The seed itself contains all the nutrients it needs to get out of the soil and grow it’s first “seed leaves”.
Depth to Plant Seeds
The general rule of thumb for seed planting depth is twice as deep as the seed is wide.
So if you have a tiny little seed, such as a broccoli, you will be planting this a very small way down, say 0.5cm. If you have a pea which is a large seed you will planting that with more depth, like 1-2cm.
Make sure the soil is well watered before you put your seed in, otherwise when you add water your little seeds may get washed around and not end up at the depth you set.
Planting too deep is another common reason for failure to flourish, as the little seed may run out of energy before it breaks the surface into the light.
Caring for Seedlings
Once planted seeds need water and light to thrive. I recommend keeping a tray with 1cm of water under the seedling pots, to ensure they have constant moisture and are not saturated. This “bottom-watering” rather than pouring over the top of plants is much less disruptive to newly forming plants and you don’t risk breaking fragile new roots.
Natural light is absolutely the best option but if the weather doesn’t permit you to keep your seedlings outside, try indoors next to a north facing window. You’ll need to regularly rotate the seeds so they don’t stretch towards the light.
Alternatively invest in a UV grow light system, and position this very close to your plants, shifting it higher as the plants grow.
As the plants start to grow their proper leaves, they will need nutrition from the soil which will mean either potting up into compost, planting out into your garden or feeding with a liquid fertiliser.
Hardening off
Once your seedlings are alive and have their first few leaves, it’s a good idea to get them acclimatised to the outdoor environment. If they have been started indoors, get them outside during the day to experience the sun, rain and breeze. This helps them grow strong and ready for their upgrade to the big vege garden outdoors! Avoid any days with very cold temperatures or very high winds until they get established.
If they’ve been growing outdoors all along, there’s no need for this step.
Troubleshooting
As you get started with growing from seed, you may run into a few challenges and this is normal! Here are our most commonly encountered issues, and their causes.
Germination
Low germination rates are often caused by
- Soil drying out during the germination process, so small roots not being able to uptake water.
- Soil being saturated, causing the seed to rot.
- In the case of seeds which require light to germinate (e.g. lettuce) not having a sufficient light source can cause germination to fail.
The best fix for this is sitting your seedling pots in a tray of water, allowing them to absorb water as needed but not be saturated.
Spindly leggy plants
Once seeds sprout they need access to light. If that light is too far away or insufficient they will reach and stretch for any light source and become spindly or leggy because of it.
When growing seed inside make sure they have a sunny position, or UV grow lights.
When growing seed outdoors, again ensure it’s somewhere that gets plenty of sunlight.
If you have leggy plants, it’s not the end of the world. Many plants are happy to be planted deeper (such as tomatoes) and getting their stems further into the soil allow them to reestablish their stability. Try this, but make sure you have also resolved the light situation too!
Mould or moss
If you see mould or moss forming on the surface of your soil it means there’s too much moisture. Water less frequently, or reduce the amount of water your seed pots are sitting in. Keep them somewhere warm to allow natural evaporation to take place.
Yellowing discoloured leaves
Discolouration of leaves is often a sign that your seedling is lacking nutrients (often nitrogen). As I mentioned earlier the seed contains all the nutrients it needs to get it’s first “seed leaves” out, but after that the plant will need more food either through compost or liquid feeding.
If you have yellowing leaves it’s often a sign of a hungry plant! The seedling is probably overdue to be upgraded to a bigger pot with compost included, or into the vege garden.
Get growing from seed!
I hope this has been a helpful and informative post to give you a head start on growing from seed. It’s time to get started now with our Winter Seed Bundle!
And as always we are here and happy to help answer any questions you have along the way. Happy gardening!