Growing Advice

Raising House Plants from Seeds

The principal houseplants that are easy to raise by sowing seeds are Aloe (succulent plant), Asparagus species, Begonia semper-florensundB. rex, cacti (many kinds), Clivia, Cyclamen, Eucalyptus, Fuchsia (varieties), Grevillea robusta, Opuntia, Passijiora, Phoenix (palm), Primula malacoides and P. obconica, Ricinus, Rochea (succulent plant), Saintpaulia (hybrids) and Solatium capsicastrum.

Which Compost is Best?

It is best to sterilize the compost, and it should therefore be heated in a sterilizing apparatus for 10 minutes at a temperature of 180 F. After this partial sterilization, the compost must be spread out on a bench to cool before use.

Watering a seed pan by partial immersion

A simple method of sterilizing the compost is to water it with Cheshunt Compound sterilizer. This chemical can be obtained from any seed store. It consists of a powder which, when dissolved in water, is sprinkled over the compost before or after the seeds have been sown. It is perfectly safe to use, and does not injure the smallest seedlings. Seed boxes and pots can be sterilized by this method and thereby made pest free. To make a useable seed compost, sterilize the loam then add the peat, sand and fertilizer.

Preparing the seed compost

Filter the soil mixture through a sifter and thoroughly mix. The pots or seed pans are given plenty of drainage holes that are covered with rough siftings from the compost, and the receptacles are then filled with the compost.

Press the mixture with your fingers to moderately pack it then moisten by holding the receptacle in a pail of water. The water must not come above the rim of the pot because it is necessary that the moisture should rise up through the compost. As soon as the surface of the soil is damp, set aside the pot to drain for a few hours before planting the seeds.

The depth to which the seeds are covered depends on their size. Very fine seeds, such as those of Begonia, require only a fine sprinkling of silver sand, whereas larger seeds should be covered to the depth of their greatest dimensions. When the seeds have been sown, the receptacles should be covered with panes of glass and shaded with sheets of paper.

Each day the glass should be reversed to prevent the condensed moisture from dripping on to the soil, and setting up decay. As soon as the seedlings appear, however, the paper covering must he removed and ventilation of the receptacle begun. The glass covering should therefore be tilted slightly. This is conveniently done by means of the plant label, and the amount of air is increased in this way until the covering can be removed altogether.

Pricking out the seedlings

As soon as the seedlings have developed their first true leaves they are pricked out inch apart in pots of fertile compost such as John Innes Potting Mixture No. 1, and immediately watered in. They are shaded from bright sunlight until they are established. This generally takes 7-14 days, after which they are given more light and air. The ‘cuttings’ are taken in the usual way, by severing them just below a node (where a leaf is inserted in the stem). They are then fixed in the mouths of small-necked bottles where they remain suspended. The bottles are filled to within a fraction of an inch of the top of the necks with water, preferably rain water.

To prevent green scum (algae) forming in the water, it is best to place a few small lumps of charcoal in it. If this operation is done in the spring, the bottles of ‘cuttings’ can be set on the windowsill, and roots will form in a few weeks. Potting must be done immediately roots begin to form.