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How to care for your cactus plants

Cactus plants are amazing plants that can survive in harsh and dry conditions. They have adapted to store water in their stems, roots, or leaves, and to protect themselves from predators with spines, hairs, or waxy coatings. Cactus plants are native to the Americas, but they can also be grown throughout the world. Here are our top tips on how to grow healthy and beautiful cactus plants here in Melbourne:

Tip 1: Choose the right position for your plant

Being from warm, often arid climates it makes sense that cacti require some direct sunlight to grow well. If kept indoors they should be placed in a sunny position and therefore make great window sill plants as they can tolerate extreme heat. However, care must be taken in the middle of summer that the temperate does not cook the plants – in hot window sills that face north watering may need to be done every second or third day in summer. Outdoors plants should be positioned in northerly or westerly facing aspects to maximise sunlight. Placement near brick or masonry walls or structures will help to maximise warmth during cooler months. Growing under plastic covers to control the rain and protect against cold, may prove helpful to allow growing cacti in almost any climate.

Tip 2: Grow in open, free-draining media

Cactus plants also need very good drainage, they hate wet feet and will rot and perish quickly in wet or poor draining soils. Garden beds heavy with clay will need to be improved with sand, fine gravel and perlite. Plants should also be planted ‘proud’ of the natural soil level to avoid water pooling at the base of the plant. Growing your cactus in pots will make it easier to control the growing conditions. Using a well-draining Cacti & Succulent Potting Mix that is specially formulated with a blend of sandy and gritty materials to allow water to move through the media and drain away. Always ensure pots for cacti have plenty of drainage and are lifted slightly off solid surfaces.

Tip 3: Water and fertilize sparingly

Cactus plants need very little water, as they can store water in their tissues for long periods of time. Overwatering can cause root rot and fungal diseases, while underwatering can cause wilting and shrivelling. The best way to water your cactus plant is to check the soil moisture with your finger before watering. If the top inch of soil feels dry, water thoroughly until water drains out of the bottom of the pot. If the soil feels moist or wet, wait until it dries out completely before watering again. Never allow your plants to sit in water.

Cactus plants also need very little fertilizing, as they can survive in nutrient-poor soils. However, a small amount of fertilizer can help them grow faster and flower better. You can use a balanced liquid fertilizer that is suitable for flowering plants, such as Maxicrop, once a month during the growing season (spring and summer) and once every two months during the rest of the year.

Tip 4: Prune and propagate your plant

Cactus plants do not need much pruning, except to remove any dead, damaged, or diseased stems or spines. You can also prune your plant to shape it or keep it compact if it becomes too large or unruly. The best time to prune your cactus plant is after flowering or in late winter or early spring. Use sharp and sterilized tools to make clean cuts, and wear gloves and eye protection to avoid injury from spines.

Cactus plants are easy to propagate from stem cuttings or offsets. Stem cuttings are taken from healthy stems that have at least one node (a swollen part where spines emerge) and one areole (a small bump where flowers emerge). Cuttings should placed on a window sill for a few days, until the cut surfaces have healed over, before being placed into dry soil until they develop roots. Offsets are small cacti that grow at the base or along the sides of the parent plant. Offsets are gently removed from the parent plant and planted in fresh potting mix.