Grow your crops from seed to produce cost-effective healthy plants for your garden.
Growing your crops from seed has several advantages over buying them from your local garden centre:
- Growing from seed can be a great deal cheaper than buying plants.
- You have total control over how your plants are raised – particularly important if you want to keep to organic principles.
- There is a much wider choice of varieties and vegetables.
You can sow seeds directly into the ground or in a propagator to transplant later.
Raising seedlings indoors
Raising seedlings indoors will put you a few weeks ahead of the normal growing season. While the soil is still cold and the threat of frost lingers, your tender seedlings will grow happily on a windowsill (with a clear plastic bag over them while they germinate) or in the relative warmth of a propagator. The best plants to start off early include:
- tender plants such as aubergine (eggplant), tomatoes, peppers and basil
- early bulb vegetables such as onions and leeks
- some brassicas such as cauliflower and calabrese (green broccoli) – to raise an early crop
Seeds that are difficult to start off (see ‘Troubleshooting’ below) benefit from a heated propagator.
Thinning and transplanting
For best results, two or more seeds are usually planted per pot and then thinned out by removing the weaker ones (being careful not to disturb the other roots). This ensures there is enough room for the stronger specimens to develop. Larger seeds (such as peas and beans) should be sown two per planting station, then, after the first ‘true leaves’ have formed, thin out the weaker seedling.
Smaller seeds can be scattered over compost in a seed tray and then thinned out to give each one sufficient space (your seed packet will tell you how much room each variety needs). Once two or three true leaves have formed on the plants they should be ready to plant in an individual container (such as a 5 cm pot) or directly outside (provided all risk of frost has passed). When transplanting seedlings to a large pot make sure that you only hold them by the leaves as it is easy to damage the plant by pinching the stem. Using a teaspoon to ease out the roots can ensure minimum disturbance to their growth.
Before you plant your crops outside, you need to harden them off. Hardening off allows the plants to acclimatise to the colder conditions outside. To harden seedlings off, move the propagator or pot outside during the day and bring it in again each night. Do this for five days and then leave the plants outside during the night for two nights. They will then be fully adjusted to the cold conditions when you plant them in the soil.
Planting out should not be left too late or your young plants will become ‘leggy’ due to the reduced amount of light on a windowsill or inside. However, this has to be balanced with the possibility of a late frost which could kill seedlings off after all your hard work!
How you plant out your crops depends on the variety. For example Brussels sprouts require firm soil around their stems whilst leeks and cabbages do well if ‘puddled in’ (where the planting hole is filled with water and allowed to drain several times before the soil is replaced).
For all vegetables, it is worth preparing the soil by digging the plot over thoroughly, removing all weeds and weed roots and raking the ground level.
It helps to plant out your crops in the late afternoon on a cloudy day so they avoid the heat of the midday sun and the sudden temperature drop of clear nights. After planting, your plants may initially droop but they should perk up soon if kept well watered during the first few days.
Watering
Seedlings and young plants can be delicate and require special care when watering. Seedlings should grow in moist compost. Water by misting the plants with a spray so they don’t drown or get washed away. Crops which have been recently planted out also need special care. Ensure the ground doesn’t get waterlogged or dry out. For a gentle dousing, water your crops with a watering can with the rose upturned.
Direct planting
Some vegetables (such as root crops and legumes) prefer to be planted directly in the ground in their final growing positions. These vegetables include:
- peas and beans
- root vegetables such as beetroot, carrots, parsnips and turnips
- sweetcorn
Root vegetables are generally hardy (relatively resistant to the cold) so can be sown directly into their final growing positions in spring. Legumes (such as beans and peas) and sweetcorn can be sown directly into the soil in early summer or grown in biodegradable coir pots that can be transplanted into the ground with the plant (this avoids root disturbance, which can halt growth for a few weeks).
Some brassica crops actually benefit from being transplanted. For example transplanting Brussels sprouts helps them develop a robust root system. This is particularly useful if your plot harbours the common club-root fungal disease. Seeds can be sown in rows in a seedbed (a nursery area where you start off plants as seeds) and then transplanted later.
Whenever sowing outside, it makes sense to sow in rows. This will help you distinguish your seedlings from other plants – essential when weeding to give them room to grow in the early weeks. You may choose to plant in long rows making a furrow at the depth specified by the seed packet. Space seeds according to the instructions given and thin out the weaker seedlings once they have emerged. Cover the seeds with a fine layer of soil and gently firm them down. Then, water.
Alternatively if your garden is divided into beds you may wish to sow in small rows to concentrate more seeds into a smaller area. The rows have less space between them and crops have slightly less space between plants.
Troubleshooting
Certain vegetable seeds can be tricky to get started. For example coriander and parsnips take a long time to germinate. You can speed up the germination of coriander by gently pressing the seeds with a brick, or in a pestle and mortar. This will open the seedpods slightly, allowing the plants to escape from them more easily. Because parsnips take so long to geminate, weeds can grow and it is difficult to spot the emerging parsnip seedlings. Often gardeners accidentally remove them, mistaking them for weeds. A good trick is to pop a radish seed in the planting hole with the parsnip seed. The fast-growing radishes will mark the spot from where the parsnips will grow and be long gone by the time the parsnip seedlings emerge
Summary
- Growing from seed can give you more choice and cost less than buying plants.
- Crops can be raised from seed in a propagator or directly in the ground.
- Brassicas (such as cabbage and Brussels sprouts) benefit from being transplanted.
- Root vegetables (such as carrots, parsnips and beetroot), legumes (such as beans and peas) and sweetcorn don’t like being transplanted and are best sown directly in the ground or in biodegradable pots (to plant out later).