This, however, was entirely beneficial. Within about six months every desk sported at least one pot of African violets, with much sprightly conversation about which needed a bit more sun or the best ways to water them, not to mention discreet flower counting as everyone tried to work out whose plant had the most blooms.

The office African violet outbreak was sparked by a single enthusiast, who brought in several magnificent plants, totally filling their large pots and covered in spectacular flowers. African violets bloom best when slightly pot-bound and these beauties must have been growing for years, their blooms in various shades of mauve to fuchsia or dappled with white. The first sign that a passion for African violet was beginning to spread was when she passed a couple of leaf cuttings to a young clerical assistant, to show her how something as impressive could be grown from a single leaf.

It truly is magically simple. First pick off a leaf with about 3cm or more of stem. If you want to watch the roots form, take a bottle with a narrow top, fill with warm water, cover it with plastic or carboard, fasten it to the top of the bottle, cut a hole in it and insert your leaf stem. Keep the bottle in a warm spot about a metre from a sunny window. You'll see roots develop over the next three weeks or so. There'll be leaves about a month after that. It's now ready to plant.

Or plant your leaf stem straight into the spot. Fill a pot - small, and with good drainage holes - with potting mix. There are specialist African violet potting mixes but I've seen good results with just plain healthy soil. Insert the leaf stem. Water well with warm water. Now either tie a plastic bag over the pot to reduce evaporation, and keep it in the warm sunny spot as above till it begins to grow leaves, or do without the plastic bag, and just water the pot as needed. You may find you have propagated several tiny African violet plants from the one leaf. If so, separate gently and plant.

You can, in fact, translate all of the above to 'take a leaf and bung the stem in a pot'.

African violets are the perfect office desk plant. They like a constant temperature, and should be kept about half a metre to a metre from a window - turn them often so each side will get its dose of sunlight. They also need little water - overwatering can kill them - so the pot must be well drained. Water only when the top feels dry, and definitely water when the leaves begin to droop. 'Little and often' is a good rule, and warmish water, not cold. Don't get the leaves wet. You can water the soil directly, or by placing the base of the pot in water till the top feels slightly moist.

African violets also like humidity, which is hard to come by in most offices, but can be helped by growing a half dozen pots of African violets together to raise the room's humidity. If the leaf edges turn brown from too dry air, fill a saucer with ornamental pebbles, half covered with water, and put the pot on top of the pebbles so the base of the pot isn't in the damp. Then when you need to water, add a little more to the saucer - just enough to touch the base of the pot.

Once you have planted your leaf and stem you should have a decent looking plant in about two months, but it will take longer than that to flower. Feeding and sunlight usually mean a better display of blooms. If your plant is being stubborn, I've heard that covering the plant with a paper bag for four days may shock the plant into blooming when the bag is removed. This sounds a bit too much like African violet torture, and I've never tried it, nor had to.

There are special fertilisers for African violets, which should be applied well diluted, though many happy African violets manage for at least a few years without being fed. The most glorious specimens, however, have probably been fed a little every fortnight. Remove dead leaves and flower stems to keep it neat. If the leaves get dusty, brush them very gently with a soft paint brush.

Then pick a leaf, and pass it on...