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Incorrect watering is the major cause of houseplant problems. Get this right and you are much more likely to have a healthy houseplant.

Some plants cannot stand having water on their leaves, others like to be sprayed with water regularly. This article will tell you how and when to water,

Feeding your plants correctly is also necessary but there are several methods of doing this. We let you know how and when to feed your houseplant.


How to Water Your Houseplant
The majority of houseplants prefer to have a good soaking with tap water, then to be left alone until they almost dry out. However, see the exceptions listed later in this article. Watering can be from the top or from below. In general watering from the top is most convenient but if you suspect the soil is very dry, leave the plant in a a few centimetres (an inch or so) of tepid water for half an hour. By this time the top of the soil should have become moist and the plant should be removed from the water and placed where any excess water can freely drain away. Watering very dry compost from the top may not give all the compost enough time to soak up sufficient water.

When To Water Your Houseplant
Once you become used to the weight of the houseplant you can tell if it needs to be watered just by holding it and judging the weight. Another method is to feel the top of the compost. The final easy method is to insert a small knife in the compost - if the knife comes out dry with no moist particles of compost on it then the plant needs watering.

Which Water To Use
Water straight from the tap is OK for watering most plants but a better alternative is to fill a jug with tap water and leave it to stand for 30 minutes or more before using it. This will allow much of the chlorine to disappear and bring the water nearer to room temperature. Note that hard water areas have lime in the water at the correct level for watering most houseplants.

Lime Free Water and Misting

Some houseplants (principally orchids, azaleas, gardenias and carnivorous plants) dislike lime. In this case, filter the water first, then boil it and water the plants when the water has reached room temperature.

Boiled water is also good for mist-spraying because it does not leave chalky marks on the foliage. Other sources of lime free water include rainwater and melted ice from the freezer.

Gardenia jasmenoides, click to enlarge


Misting plants using lime free water provides a humid micro climate and cleans the pores of the leaves. Misting twice a week is beneficial for many houseplants but read the requirements for each individual plant because it can harm some.

Feeding Houseplants
New compost used for houseplants contains fertiliser but this is all used up by the plant within about six weeks. After that most houseplants need regular feeding to keep them healthy. There are a variety of products for this purpose including ready mixed liquid feeds, powder which added to water, granules scattered on the surface and stick or granules which can be pushed into the soil.

Our recommendation is the ready mixed liquid feeds because the amount is easily regulated and it's easy to place a few drops into the water when watering your plants. The powder is OK but it is easier to get the dose wrong with this method. The granules and stick deliver only a very localised feed and have the potential to damage the roots. There are also foliar feeds (ready mixed feed which is to be sprayed onto the leaves) but these are messy and it is very difficult to get the dosage correct.

Some plants have special feeding needs and these will be stated on instructions that come with the plant. They are also described in the requirements for each individual houseplant (see right hand column). Houseplants to be careful with include air and carnivorous plants which need no feeding. Cacti and succulents, orchids and bromeliads need infrequent and very weak concentrations of feed.