Cacti are a diverse group of plants and are well-known for their spectacular flowers, dramatic
sculptural forms and their beautiful, often formidable spines. Many have evolved to survive harsh, dry desert & mountain environments, which makes them well-suited for indoors planting. Although many
species can withstand considerable neglect, they will grow better, flower more profusely & live longer if the following ‘rules’ are observed.
Watering - Plants should be given a good soaking & then allowed to almost dry out.
This will depend on:
- Aspect – cacti on a sunny, north facing window may require soaking twice a week in summer, compared to once a month if it is cool & sunless (winter).
- Potting mix – will need to be open & well-draining. Cacti and Succulent mix is recommended. Never allow pots to sit in a saucer of water.
- Season – most species like to remain dry over the dormant period (winter). They require most water when they are actively growing (spring & summer).
- Sunlight – is essential for better shape, flower & spine formation. The spines protect plants from sunburn. Hairy & closely spined species require the brightest light.
Plants on windowsills will grow & flower more symmetrically if they are rotated regularly.
• Slow release fertiliser which is low in nitrogen, is best for healthy, strong growth & good flowering. Only feed when the plants are actively growing (i.e. not in winter).
• Larger, fast growing varieties require more feeding than smaller, globular ones.
Most species are tolerant of temperature extremes & will survive cold Melbourne winters as long as they are kept dry. In fact, a cool, dry winter will often promote better spring flowering. (NB.
Melocacti are notable exceptions & are best kept indoors in winter.)
|Poor colour (red caps)||Poor lighting|
|Rotting / collapse||Over watering|
|Elongated shape||Poor lighting|
|Scarring||Sunburn, mechanical damager|
Spray with Eco or Pest Oil
|Mould infections||Spray with Eco fungicide. Allow offsets to callous for one week before re-potting|
Pests and Diseases
|Red Spider||Raise humidity and ventilation (i.e move outdoors), regular detergent sprays|
|Mealybug||Dab with methylated spirits if minor, spray and/or drench with Confidor if major|