at the requisite size for planting out so that they will make a significant impact when in flower.
The sequence of bedding plant sowing is governed primarily by the speed of germination and subsequently by the growth rate of the seedlings of each species. Thus slow-developing plants are sown early in the year
4 Mix small dust-like seeds with some dry, fine sand to extend the seeds.
5 Broadcast sow the seeds thinly, keeping hand close to compost surface.
6 Sieve just enough compost over the seeds to make an even cover.
7 Label the container with name of plant and date of sowing.
8 Water in a fungicide to prevent damping-off diseases.
9 Cover container with a pane of glass. Stand in the warm (21°C/70°F).
—-although it is important to remember that in the very early part of the year light intensity is usually poor and growth rates of seedlings will be proportionately depressed.
Sow bedding plant seeds in a pan (dwarf pot) or a seed tray depending on the quantity of seed used. Because the seeds germinate relatively rapidly at warm temperatures, peat-based composts are quite satisfactory, and there are many proprietary brands available. Fill the container with compost, but keep it light and uncompacted so that drainage is maintained. The main problem with peat-based composts is that they tend to waterlog easily, causing both death of the seeds and poor seedl i ng development—symptoms often associated with damping-off diseases and sciarid fly attacks.
Many bedding plants, for example lobelia and Begonia semperflorens, have incredibly small, almost dust-like seeds that are difficult to sow evenly and at a sufficiently low density. These should be thoroughly mixed with some dry, fine sand, so that an even distribution can be achieved. Covering with compost is not then necessary.
With the seed packet close to the container sprinkle the seeds evenly over the compost. Sow thinly to avoid having overcrowded seedlings later on. Sieve just sufficient com post over the seeds to make an even cover. Label the container and water the seeds either by using a fine rose on a watering can or by standing the container in a basin of water. Add a fungicide such as Captan to the water. Cover with a sheet of glass to conserve moisture and place in a warm environment (21°C/70°F) to promote germination; at this stage light is not important.
As soon as the seedlings emerge, place them in the light to encourage growth and remove the cover because excessive humidity among seedlings at this stage will lead to damping off.
The temperature, however, should still be maintained at as warm a level as possible to encourage quick growth to a size at which the seedlings can be pricked out.
As soon as the seedlings are large enough to handle, prick them out into individual pots or seed trays. Their growth will inevitably be checked when they are transplanted, but the smaller and less branched the root system is, the less damage and therefore check will be experienced.
The main problem will be the likelihood of damping-off diseases. This can only be avoided by scrupulous hygiene, light sowing densities and regular sprays with fungicides such as Captan or copper-based chemicals.
10 Remove glass as soon as seedlings appear. Place container in well-lit area.
11 Prick out seedlings into individual pots once they are large enough to handle.
SEQUENCE OF SOWING January to February
Antirrhinum; Begonia semperflorens
February to March
Dahlia; Petunia; Saipigiossis; Salvia
Ageratum; Alyssum; Lobelia;
Mesembryanthemum; Nemesia; Scabiosa; Tagetes—African
March to April
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