Growing Tips

Advice on growing and caring for your plants

True Cacti & Other Succulents

On receiving your plants they should be potted up in any John Innes compost, or any peat-based pot plant compost or one of the modern, less environmentally dubious alternatives like coir; you can add extra drainage material in the form of horticultural grit or sharp sand, but this is not essential.

After potting up your plants, leave them for two or three days before watering (except in winter, when water should be withheld until spring, as winter is their dormant period).

Any frost-free sunny place will satisfy the majority of plants, provided they are kept dry in winter. A greenhouse, though desirable, is not essential, since many plants will thrive and flower regularly on sunny windowsill, and will give you a great deal of pleasure.

Cacti and succulents, being drought resistant, are also tailor made for the modern conservatory, where you can create an unusual and attractive display without the work and worry of water-guzzling plants.

Cacti are justly popular with collectors as they are so easy to grow and care for, and they come in a multitude of interesting shapes and sizes with a variety of spine forms and colours.

Many of them will also reward careful cultivation with magnificent and brightly-coloured flowers.

Once a plant is old enough to flower it should do so every year, generally in the spring or early summer.

The Rebutias, Mammillarias, Lobivias, Notocacti, Epiphyllums (Orchid Cacti) and Christmas cacti are particularly good for flowers and some will flower more than once in the same year.

Rebutias flower frequently and easily

During the winter all cacti (except Christmas cacti) should be kept dry from around November to March.

In the spring a little more water should be given and the amount increased gradually, until the plants are being watered once or twice a week by the summer. When they are in full growth they will appreciate feeding every two or three weeks with Chempak, or any other specially formulated cactus fertiliser; tomato fertilisers are also suitably formulated.

In the autumn the watering is gradually reduced again, in order to rest the plant during the winter; this also encourages the plants to flower in the following year, as they need a period of dormancy to produce their buds.

Succulents, which include Lithops (Living Stones), Crassulas, Echeverias, Sedums etc., differ from cacti in generally having leaves rather than the spines surrounded by hair which are characteristic of true cacti.

They come in a truly astounding range of shapes and colours, and the plant bodies vary widely in colour from speckled red on grey to lush yellow and green.

Crassula Falacate

Some species have a delicate grey “bloom” upon them which is often tinged red by strong sunlight.

The other succulents require similar care to cacti although, in general, they need less sun and a little more water, and they are rather more vigorous in their growth. Lithops are the exception in that they relish a sunny position and dislike over-watering!

The popular Lithops or “Living Stones” should be planted so that they just emerge above the level of the compost, and they grow best in a sunny position. They respond to weekly watering and a monthly feed with a cactus fertiliser like Chempak.

Their large, daisy-like yellow or white flowers are produced in the autumn up to November or December.

After this they should be given a rest, as with other types of succulents. In the spring, when the Lithops begin to grow again, the outside segments of the stem die off to be replaced by new growth from the centre. Lithops can be displayed to great effect in a group planting amongst pebbles, where their camouflage can be truly appreciated!

All of these plants appreciate a peat-based compost – or its modern equivalent – and they respond well to regular feeding.

Epiphyllum Hybrids (Orchid Cacti) are grown for their huge, spectacularly beautiful flowers, which are available in a wide range of colours apart from blue.

Their ancestry can be traced back to epiphytic cacti, rooting in the branches of trees in tropical rain forests, where pockets of moisture and decaying vegetation collected.

Because of their origins, they need more water than the terrestrial cacti and a shadier position – perhaps under the greenhouse staging, or on a fairly light windowsill.

They also benefit from liberal feeding with any pot plant fertiliser, or with a tomato fertiliser, which is particularly suitable, in the growing season, though they should be grown “harder” if you find they are shy to flower.

Ideally they should be kept at temperatures above 40 degrees F.

Aporocacti, Aporophyllums and Selenicereus require similar treatment to the Epiphyllums, though the Aporocacti are somewhat hardier and prefer more sun.

All of these plants need plenty of water and feeding during the growing season.

Christmas Cacti should be kept shaded from prolonged direct sunlight, and they do well as houseplants or under the greenhouse staging. They should be watered just before the compost completely dries out, but they should not be given so much water that the compost remains saturated for long periods. They can be fed every two weeks or so.

Christmas cacti are tolerant of low temperatures, down to about 35 degrees F. (at least for short periods), but if you wish to flower them in the winter months, they should be kept above 45 degrees F.

Some of the colours, e.g. white, develop pink flushing at lower temperatures, so they should be given temperatures of 55 degrees F plus to flower in their true shades.

The winter flowering types are short day plants and need about ten hours of darkness to induce bud formation. Fortunately this condition arises naturally in the autumn, provided exposure to strong artificial light is avoided during the night.

Pests etc

The most common pest encountered on cacti and succulents are little insects called mealy bugs, which look like little bits of cotton wool.

Mealy bug

Mealy bugs can occur on the roots, stems or leaves and although they are unlikely to kill plants, they do look unsightly.

Fortunately they can easily be eradicated by using Intercept – although this is marketed as a vine weevil killer it is also brilliant against mealy bug.

Overwatering is the main cause of cacti dying and even this is difficult to achieve in the summer months with well-established plants.

The winter is the dangerous time, when the plants have stopped growing and evaporation from the pots is slow. These plants do not have a natural resistance to moulds etc., and, although it sounds harsh, we recommend that very little or no water is given in the winter, which will ensure that your plants survive to give you pleasure for many more years.