How to grow hardy cacti and succulents

Most hardy cacti and

A group of plants that have thick, fleshy leaves or stems that are able to store water. This allows them to survive in arid habitats with low moisture.

RHS guide to growing houseplant cacti and succulents

RHS guide to growing houseplant cacti and succulents

Continue reading for specific tips on overwintering hardy cacti and succulents outdoors and any problems you might encounter.

Further details on individual species growing guides can be found in RHS Find a Plant with a list of stockists.

You might try the British Cactus and Succulent Society for further advice on specific species and cultivars.

Overwintering

Getting your plants ready for the winter is vital for their survival. Here are a few notes specific to overwintering cacti and succulents;

• Some plants such as the Opuntia will benefit from a covering of a heavy duty plastic or bubble wrap to keep out the winter wet as well as the cold
• Plants that are de-hydrated will be hardier. Allow pots and specimens to dry out slightly before you wrap them
• Bubble wrap containers that cannot be brought inside, to help prevent the roots from freezing
• Plantings that are at the foot of a wall, by an airbrick or under the shelter of an eave will stand a greater chance of survival
• When using non-breathable plastic and bubble wrap, never wrap the plant too tight. Allow for some air circulation
• Give the plant a good tidy up before wrapping; remove fallen leaves, debris and dead foliage. This helps to prevent decay

Pests

Mealybug occurs as white patches on stems and bronzed areas may indicate glasshouse red spider mite. Scale insects cause patching on stems and leaves.

Diseases

Cacti and succulents suffer from rots such as Erwinia, fusarium and botrytis. These are caused by insufficient or excess water and cold temperature. Try to treat with a fungicide as soon as you see the infection and improve growing conditions. However, they can be difficult to control.

Poor cultivation

Overwatering will stunt growth and cause blistering due to oedema; prolonged overwatering with eventually lead to rot. Underwatering also limits growth and causes shrivelling. Affected plants will become misshapen and scarred. Lack of light produces weak and misshapen specimens and cold damage produces patches on the surface.

Cactus corky scab is a common problem where growing conditions are too humid or bright.  Brown or buff patches form on the skin of the plant and gradually shrink to form a scab surrounded by unaffected areas.  Gradual reduction in humidity and light can prevent further scabs but abrupt changes can make the problem worse.