Although correct watering should be easy, it is responsible for the death of more houseplants than anything else. Too much water poured regularly into the compost can cause plant roots to suffocate and rot.
Most people overwater their houseplants - ‘killing them with kindness’! Remember to check that the composts is drying out with your finger before watering. Or lift the pot to check the weight and whether it is light and therefore in need of watering. Frequency of watering will vary throughout the year, depending on the plant’s growing conditions.
Water when the compost is drying out, not on a rigid pattern of say every Monday, Wednesday and Friday. Few plants appreciate permanently wet compost and the surface should be allowed to dry out between watering.
Only a few plants need permanently wet conditions. These include azalea, umbrella plant (Cyperus) and Acorus. Always use tepid water that has been allowed to gradually come to room temperature. Don’t use freezing cold water straight from the tap. Azaleas, citrus trees, heaths and heathers are lime haters and in hard water districts try to use rainwater. Alternatively, add a teaspoon of vinegar to a gallon of hard tap water and allow to stand overnight before watering ericaceous specimens.
Most plants with stems can be watered from above in the normal way. However, some plants grow better when watered from below. The stems of African violets, for example, are soft, flesh and hairy, and the growing crown can easily rot off if regularly wetted.
Similarly the tops of cyclamen tubers should be kept dry to reduce the risk of grey mould disease attacking flower and leaf stalks. These plants are best watered from the saucer below, tipping away any excess after 15 minutes.
Watering from above: Ideal for most plants
- Place the pot in a saucer and pour tepid water onto the compost.
- After 15 minutes tip away any excess water left in the saucer under the pot.
Watering from below: Ideal for African violet, gloxinia and cyclamen
- Pour tepid water into the saucer below the pot.
- Leave until the surface becomes moist (approx. 15 minutes), then tip away any remaining water.
Too much water
Leaves wilt and turn soft, finally old and young leaves fall. Rotting of stems and plant crowns. Roots are brown and rotten.
Too little water
Leaves wilt and plant shows little growth. Leaf edges brown and dry. Old leaves fall first.