How to raise seedlings
This is a brief practical guide to raising seedlings. This will usually be enough to start, but if you want to learn more, see the Raising seedlings page.
Sowing directly vs sowing in containers[edit | edit source]
If you have a mild climate, and especially if you like lazy gardening (which is really efficient and resilient gardening), then planting directly into a garden is often best. The seeds can be planted directly in a small amount of compost or potting mix, unless the soil is both good quality and light.
Container gardening is more flexible than garden beds - you can sow seed in the container, and move the container from a very sheltered position to a more exposed and sunny position when it's ready. (Not too exposed of course! See how the plant copes with the wind and sun.) ideal for urban locations with limited space. Lettuce, baby spinach and other greens can be grown in a window box or pot. Cherry tomatoes or dwarf tomatoes can be grown in a pot on a porch in a balcony garden. Even if the number of plants is small, you'll enjoy the freshness of the produce.
Seedlings let you plant earlier in the season (during colder weather, or when the beds are not yet ready). It gives you a head start.
Sowing in containers[edit | edit source]
- Small growing containers. Use egg cartons, washed-out food containers (e.g. yoghurt or butter containers, or unwanted take-away containers), store bought trays with growing cells, or tiny compostable pots. If using a food container, just poke a few holes in the bottom of containers for drainage.
- Trays or corrugated metal sheets: Use these to catch excess water.
- Soil, compost or potting mix: Light and fertile soil is best - but avoid freshly applied manure or other fertilizer.
- Get these from a shop, a seed savers network (who may have more interesting and locally suitable heirloom varieties), or from
- Easy seed suggestions include mixed leafy vegetables, which can be eaten young - e.g. lettuce, spinach, rocket (arugula), silverbeet (aka chard), and nasturtiums (use small amounts of the leaves and flowers in salads). Also broccoli, cherry tomatoes, amaranth, chillies (aka peppers), capsicum (aka bell peppers), cabbage, beans (dwarf/bush varieties) and herbs (e.g. thyme, coriander, and basil).
- Labels: unless you're very confident of your memory, or ability to recognize the seedlings, use labels! Writing on popsicle sticks, or cut up strips of plastic from a yoghurt container (using a permanent marker) and stick the labels in the edget of the pot or tray. Don't use paper or cardboard, as water will destroy it.
Planting depth: Seed is usually planted at a depth of 1.5 to 2 times the width of the seed. If there are instructions on the back of the seed packet.
If you are sowing directly in a larger pot or garden bed, and the soil is not porous enough for seeds, add a little compost or potting mix where you are planting the seeds.
Needs of the seedlings[edit | edit source]
Seedlings and freshly planted seeds need careful attention. Keep them protected from wind and sun which dry them out. Specifically, they need:
- Water Perhaps put freshly planted containers inside a plastic bag in the beginning, with openings to allow oxygen in. This is an easy miniature greeenhouse and will also store heat overnight, and become warmer than ambient temperature if it is exposed to sun. Or place under a plant igloo.
They will usually need watering daily, even several times a day if exposed and in hot summer weather.
- Alternatively, moisten seedlings with a spray bottle, every day. When they are a few days old, they may cope with careful watering using a fine nozzle on a watering can or hose. When the seedlings have emerged, and they have a root to help find oxygen and water, you can fill the tray with a shallow layer of water, and this may be enough.
- Oxygen - this is not a problem as long as the potting mix or soil is light and porous.
- Temperature - most vegetable and herb seeds will sprout best at temperatures around or slightly above room-temperature, 16-24 deg C (60-75 F). They can be a bit higher or lower and you can still successfully grow, but very cold or very hot temperatures will be a problem for many vegetables and herbs. In such conditions, you need to look for a more protected position especially while young, and look for species and varieties which are suitable to your local conditions.
Notes and references[edit | edit source]
- i.e. ignoring the first leaf or two when they sprout, which look different from their normal leaves