Why Grow from Seed?
Growing plants from seed is relatively easy and very cost effective. Whilst you will need to make an initial outlay, once that’s done you can grow your own from each packet of seed time and time again.
Most seed packets are under £5 and contain multiple seeds, sometimes in the hundreds and whilst you cannot guarantee every seed in the packet will germinate, getting lots of plants for the cost of one full grown one is great value, although obviously you need to balance this against your time in sowing and looking after them. There is no greater feeling than picking that fresh flower or eating that fresh vegetable that you have grown from seed.
What Do I Need?
As mentioned above, there are some tools that are required for growing seeds, as with all gardening as you become more involved this list can grow but the basics are:
Seed Trays – come in different sizes and materials but preferably something strong and stable and with holes in the bottom to allow drainage. There are variations with individual cells to plant into or with small pots, these tend to be better for larger seeds, like tomatoes or cucumbers where you will grow one or two per cell/pot. You can also make your own by using newspaper or toilet rolls.
Growing Media – for seeds, whilst normal multi purpose compost will work, its better to use specialist Seed Purpose as it had been created with the specific needs of a seedling, this will help improve survival after germination. You may also need perlite/vermiculite or gravel depending on what seeds you are growing and what the best soil conditions are, although usually this is more for when you start to ‘pot on’ the seedling.
Its best practice to sieve your seed compost before you fill the tray to remove any large lumps of compost that may be present, so a fine garden riddle is also useful at this stage
Dibber – basically something to make the hole to put the seed in. Again the larger seeds normally need planting a few millimetres deep and whilst you can use your finger or a pencil, a purpose made dibber makes things just a little easier
Tamper – something you can use to tamp down the compost once you have sown the seeds. You can use the back of your hand or the bottom of a similar size pot but a small block of wood is ideal
Plant Labels – it’s really important to label the seeds as you go along, young seedling looks very much like another. Ideally chose a label that can either be composted or re-used many times, and write with a removable pen or a pencil
Propagator Lid – depending on your seeds, you may need to cover the tray and the easiest way is with a propagator lid, these will come in the same sizes as your seed tray and fit nicely onto the edges of the seed tray. These can be bought as all in one kits, with the lid and tray together, some also coming with the ability to plug them into the mains so that they heat up, giving the seeds an even better boost towards their germination.
When to plant the Seeds?
All seed packets have information on them that suggest the peak time to sow them either indoors or outside. They will also indicate any preparation that the seeds need to ensure the best chances of germination, some require scraping or soaking before sowing as they have a harder outer shell.
When planning your garden or veg patch you also need to consider how many of your plants you want to come to maturity at the same time, if your planting lettuce for example, you don’t want 50 all to be ready to harvest at the same time, it would be preferable to have 10 ready each week for 5 weeks, this is called succession sowing and is particularly important for the quicker growing summer crops, like salad leaves, carrots, spring onions, radish. Whilst the initial crop of plants are again ideal to start of indoors, meaning you are further towards harvest when the frosts ends, direct sowing after that gives the desired succession effect and leaves the indoor seed area free for later season crops.
However, if your growing summer flowers, say cosmos, then having all the plants coming into flower at the same time would give a great display with regular deadheading leading to repeat flowering preventing the need for successional sowing.
Why Plant your Seeds Early Indoors or a Heated Greenhouse?
Starting your seeds off early either indoors, in a heated propagator or a heated greenhouse is a great way to get ahead of the seasons. Normally it gives you faster and more reliable germination that direct sowing in the ground, along with protection from the weather and insect/slug damage.
Whilst all seeds can be sown indoors, there are some where the benefits are much higher and these are the ones to focus on. These include:
Tender plants – those that are not frost tolerant, including both summer flowers and edible crops, for example, tomatoes, cucumbers, cosmos and some herbs like basil
Annual Climbers – these can be sown direct but starting them off indoors means that once the outside conditions are right for growing, you have a strong plant raring to go. Examples include Sweat Pea’s, Morning Glory and of course Runner Beans.
Late season Vegetables – in the middle of the growing season, your valuable ground will be covered with you summer crops, by sowing in autumn or overwintering veg indoors or in the greenhouse you can ensure that you have plants ready to take the place of your summer stars straight away and are established before the colder weather arrives. Examples include Brocoli and Spring Cabbages.
How to Plant Seeds
1.Fill your seed tray to the top with growing media, having mixed in any extras recommended by the seed packet.
2. Tamp the soil down, gently firming the compost and ideally leaving a 0.5-1cm gap from the top of the tray. Be careful at this stage as you want to ensure the seed has good contact with the compost when its sown but ensure that it is able to penetrate the compost with its roots.
3. Follow the instructions on the seed packet for sowing, either sowing individually, in a drill or sprinkling on the surface. It’s often easier to empty some of the seeds into your hand and then pick them from there rather than trying to get them direct from inside the packet.
4. Once you seeds are in place, top the tray up with more growing media, ensure to cover the seeds as required.
5. Its time to water, the easiest way is to stand the tray in water and allow the growing media to soak up the water through capillary action, but if this is not an option for you, use a watering can but with an inverted fine rose so its upside down and water very gently, you don’t want to dislodge any of the seed, if the water is pooling, its likely the seed will be to.
6. Pop the label(s) into the tray, taking care to avoid any seeds. Make sure the name is clear on the visible part of the label and add the date they were sown.
7. Cover with the Propagator lid/place inside the heated propagator. This is to try and conserve the moisture as well as creating heat.
8. Finally place them in their growing location, either a greenhouse or a south/west facing windowsill. Check the seed packet for the ideal temperature but a minimum of 18 degrees is normally required for germination.
Once this is done, you have a few days to relax, or just sow more types of seeds.
What Happens Next?
1. Check the tray(s) regularly for any signs of germination, once the seedlings have started to appear then remove the propagator lid
2. Keep the tray in a bright and warm area.
3. Keep the growing media moist, it should never be allowed to dry out but doesn’t want to be over wet.
4. Once the seedlings have got big enough to handle, consider potting on to prevent overcrowding if you have planted in trays, or into larger pots if they are planted individually in cells or smaller pots to ensure they have the nutrients and space needed to keep growing.
5. Don’t be in a rush to plant them straight out. For most, ensure that the risk of frost has gone and harden off the plants outside so they can acclimatise before being planted into their final growing space.