Happy Cactus (Dorling Kindersley, 2018) unearths the secrets of different cacti and succulents, with profiles on more than 50 popular varietiesCacti and succulents have a rather different watering and feeding regime to most other houseplants – timing is everything.
When to Water
Cacti and succulents will thrive and flower if you mimic the seasonal rainfall pattern in their native habitat.
Water your cactus every two weeks or so during its growth period. In the northern hemisphere, this is from April until early September.
Winter Rest Period
From early September, gradually reduce watering, stopping altogether during the plant’s winter rest period – from early November to the end of February. Gradually commence watering during March.
Exceptions to the Rule
Winter-flowering cacti need to be watered every two weeks or so (and be kept warm) until they finish flowering in late autumn or early winter.
How Much Water?
Overwatering leads to root rot , which is the main cause of death in cacti and succulents. However, by following a few simple steps you can prevent this from happening:
- Make the potting soil moist but not wet, and allow all excess water to drain away after each watering.
- Allow the compost to become almost dry between waterings.
- Check the moisture level of the compost by sliding a label or knife blade down the inside of the pot – if it comes out clean, the soil is dry.
- Remember that compost in plastic and glazed ceramic containers retains moisture for longer than it does in terracotta pots, so you will need to water slightly less frequently.
How to Water
Most plants can be watered from above. However, if your cactus has hairy leaves (eg panda plant), or its leaves and stems cover the compost, water it from below to avoid splashing them. If possible, use rainwater (leave a bucket outside to collect it), as some cacti are sensitive to the minerals in tap water. Tepid water is best.
Use a watering can with a long, thin spout to reach the potting soil easily. Water the potting soil evenly around the base of the plant.
Stand the pot in a saucer of water for around 30 minutes. Then drain any excess water from the saucer. Water is absorbed from below.
Like all plants, cacti and succulents need food in order to thrive. Add a high-potash feed, such as liquid tomato fertilizer, to the watering can two or three times during the growth period (from April to September). Be sure to follow the manufacturer’s instructions and don’t be tempted to add extra – overfeeding can damage the plant.
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From Happy Cactus (Dorling Kindersley, 2018); used with permission of publisher.