A thorough watering occasionally is better than a little frequently. The latter moistens only the top of the soil and causes the roots to come towards the surface in search of it. Most plants can safely be plunged in a bucket of water for half an hour or until bubbles stop, then stood where the surplus water can drain out freely. This ensures that water does not merely run down the sides of the pot and out at the bottom, which is what may happen when using a watering can. Those plants which hate having their leaves splashed can be stood in a saucer of water for hour, then drained.

Wick-watering is another alternative: place pots round a large bowl of water and put a length of thick cotton or wool between each pot and the water, so that the plants can continuously absorb some water (a useful device when going on holiday). Use pebbles to anchor the cotton.

Most indoor plants need liquid fertilizer in the water during the growing period, because a pot holds little soil and the nutrients in it are usually exhausted quickly.

If you can collect rain water, this is better for plants than tap water. You can also use water-softening tablets or a handful of peat left in a can of water overnight if the water is very hard. The water you use should be at room temperature.

Most plants dislike soggy soil - hence the advice elsewhere in this book to put pebbles or charcoal inside
containers that lack drainage holes. For the same reason, do not leave a pot standing in a saucer full of water. It is better to keep pots on dishes or trays containing gravel, seashells, pebbles or anything else to raise them up a little.