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Sowing and Growing Seeds Indoors

Growing From Seed
Starting seeds indoors or in a heated greenhouse is a good way to get plants off to an earlier start than nature normally allows.  The key is not to sow too many - think how large they will be in early May, and plan to grow for that size.


For really early sowings in january or February, choose plants that take a long time to develop such as begonias, antirrhinums and sweet peas. Most other annuals should be sown around March or April time.


Fill a seed tray with seed compost, lightly firm it down and water until moist but not saturated with water. Where the seeds are very small, it is best to mix the seeds with fine sand or dry compost and then spread the mixture onto the top of the moist compost. Do not cover the seeds with more compost, but cover the container with cling film  or any clear polythene. Larger seeds should be covered with roughly their own height of compost - read the seed packet for exact details.

Place the container in a shaded or dark position in a warm room in the house. The ideal temperature is 20 - 22C (68 - 72F), although the temperature in an evenly heated house should be OK. Watch the seeds daily for emerging seedlings - this normally takes about two weeks. As soon as the seedlings appear, remove the polythene and place the tray in a light position (a windowsill is suitable).  For the first couple of weeks, it is essential to keep the seedlings out of direct sunlight, it will scorch and kill them. If the window sill is cool, cover the container with a cardboard box at night, but remember to remove it each morning.  When the seedlings are large enough to handle (about 3/4 inch), prick them out from the seed tray and repot them in 3 inch pots.

Remember that they will need to be hardened off before planting out.