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Caring for Succulents

Most succulents are easy to care for if you can give them the right growing conditions caring for succulents is easier than most other plants. The two things most succulents need are plenty of sunlight and well drained gritty compost/soil.

They do not like to have permanently wet roots, and most will not tolerate frost and ice (especially if they are in wet soil).

Growing succulents in the garden

Some hardy succulents, including some Sedums and Sempervivums, can be permanently planted into well drained sites in the garden. Most of these plants are tough enough to survive the cold and wet of winters in the UK. Some sedums will die back each winter and grow again next spring.

Some tender succulent plants including Echeverias, Agaves and others can be grown outside in a sheltered, sunny, well drained site, but will probably need some winter protection in most areas of the UK. Small young succulents usually need more protection than large mature plants.

Succulents planted in the garden will usually do best in a warm sunny location. Planting in a raised bank of gritty soil and stones against a south or south-west facing wall will be ideal for many of the sun-loving succulents. It is essential that water can easily drain away from the roots and that water can drain away from the centre of the plant (so setting the plant at an angle may help). Many succulents will naturally want to grow to the side and will lean over time.

Growing tender succulents in pots will allow you to put them outdoors in good weather, and move them indoors or into a greenhouse in the winter, or during periods of bad weather such as persistent heavy rain.

A lot of succulents can tolerate quite cold weather as long as they are dry. However, if they are wet and the water freezes this can kill them. Others (such as Graptopetalum) do not like to have water on their leaves for long periods and will not grow well outside in the UK.

Choosing succulents to grow outdoors

Many succulents sold by nurseries and garden centres as “garden succulents” or “hardy succulents” are not really suitable for year-round planting in most UK gardens. So do some research before you buy your plants and before planting them into the garden.

Some hardy succulent plants suitable for outdoor growing in the UK

  • Sedum spurium
  • Sedum reflexum
  • Sedum oreganum
  • Sedum hispanicum
  • Rosularia
  • Sempervivum

Some tender succulent plants which may need winter protection if grown outside

  • Echeveria
  • Aloe
  • Agave

Growing succulents indoors as houseplants

Succulent plants can make very easy-to-care-for houseplants, as they won’t mind if you forget to water them for a couple of weeks.

If you grow succulents indoors, choose a location with good light such as a conservatory or a sunny windowsill for your succulent plants. Consider growing Sanseveria and Christmas Cactus if you need plants which will be happy in lower light.

Sanseveria are really tough plants which will tolerate a lot of neglect and will be happy in most sites around the house with reasonable light.

Many tender succulents, such as Echeveria, can make good houseplants if you have good light for them, but they will usually appreciate trips outside in summer to get some extra sunlight.

Echeveria 'Blue Curls' succulent plant
Echeveria ‘Blue Curls’ succulent plant

Some succulents usually grown as house plants

  • Sedum morganianum
  • Sedum seiboldii
  • Sanseveria
  • Kalanchoe
  • Graptopetalum paraguayense
  • Aloe (some varieties)

Light requirements for succulents

Most succulents need a lot of light to allow them to grow well. If kept in low light for too long, their growth will become pale, thin and weak (etiolated). Their leaves will look dull and lose their colours. Brightly coloured succulents especially need good light for the leaves to develop their colouring.

You may sometimes need to give your succulents some protection from very hot sun in the middle of the day at the peak of the summer. Succulents can actually get sun-stress and leaf damage in very hot sun (although that is not a big problem in the UK!).

Succulents originate from hot dry countries where there is a lot of sun (such as Mexico and Africa), but many succulents actually come from mountainous areas where they have mountain mists and rock shade to give them some protection from the strongest sun.

Low-light succulents

If you don’t have a suitable site for sun loving succulents (for example you only have North facing windows or your windows don’t get much direct sunlight) then you could consider growing one of the succulents which will grow happily in less light. Sun-loving succulents such as Echeveria will not be happy in lower light and will quickly start to look dull and lifeless.

Sanseveria (“mother-in-law’s tongue” or snake plant) and Schlumbergera (Christmas Cactus) are good examples of succulents which will tolerate low light. In fact Christmas cacti are rainforest plants, so will be happier with cooler conditions and lower light levels.

Watering succulents

Succulents like to have a good drink in summer, but they do not like to sit in water or to have permanently wet compost.

In summer: give plants a good watering at least once a week, but allow the water to drain away and the compost to dry out between watering. They may want more water in very hot weather.

It is a good idea to test the pot for moisture before watering.

  • Push your finger into the pot (under the gravel) to check how dry it is.
  • If you use clay pots, it is usually easy to tell when the compost is still very moist, as the outside of the pot will feel cold to the touch and will often feel damp and have obvious moisture on it. If the bottom of the pot feels warm and dry then the plant will probably appreciate some water soon.

In winter: reduce watering and keep plants mostly dry, with occasional small amounts of water. Gradually increase watering in spring as the light levels increase and the plants start to grow.

Overwatering in winter when the light is low will encourage weak growth, causing stems to be thin and leaves to be small and more widely spaced. Even in summer this can be a problem if the plant is growing too fast (usually due to too much water, too many nutrients and limited direct sunlight). Overwatering can cause root rot.

If possible try to water succulents on warm or sunny days.

Compost and planting medium for succulents

Succulents generally need a well-drained, gritty planting medium so that their roots do not sit in water or very wet compost. Many succulent plants originate from hot, dry areas of the world and naturally grow in grit and gravel.

Compost and grit mix for succulents
Compost and grit mix for succulents

Make your own gritty compost suitable for succulents and cacti

A gritty compost suitable for succulents and cacti can be made by combining a mix of compost, potting grit, perlite and horticultural sand.

Everyone has their own preferred mix, but this should work well, and you can try out different variations:

  • 50 – 60% compost (a fibrous compost, those rich in coir usually work well).
  • 40 – 50% potting grit/perlite/horticultural sand/crushed stone (any, or a mix of all).

To encourage new growth, re-pot or refresh the potting mix with a small amount of fresh compost each year.

Plant pots

Clay pots or plastic pots are suitable for growing succulents, but in most cases clay pots will be better.

  • For tiny plants and cuttings, small plastic pots or small seed trays are often best.
  • For larger plants it is usually better to use clay pots.

Clay Pots

  • Clay pots make it easier to tell when the plant needs watering. When the compost is damp, the outside of the pot will usually feel cold and damp to the touch.
  • When the compost is dry, the pot will feel warmer to the touch.

Encouraging succulents to develop their colours

Many succulents change their colours, and develop strong colouration in the right growing conditions. Succulent plants usually develop their best colours in late summer, and they need plenty of sunlight and less water to do this. Older plants are more likely to develop strong colours than young plants.

To encourage the plants to do this:

  • Reduce watering.
  • Don’t feed, as this encourages new growth.
    Plants which have recently been re-potted with new compost will often be less colourful than plants in old compost with limited nutrients.
  • Give plants at least 4 – 6 hours of direct sunlight a day.
  • If you keep plants indoors, regularly take them outside and place on a garden table in the sun.

Succulent pests

There are a few pests which can affect succulent plants, but some of the worst and most damaging are probably mealy bugs and weevils.

Mealy bugs

Mealy bugs cannot easily be seen with the naked eye, and often the first sign of them is a white cotton wool type material on the stems and leaves. You may also see scarring and damage on leaves and stems, and a black sticky mildew.

Isolate your mealy bug infested plant away from other plants until you are sure the bugs are all gone, as it can spread.

The damage and white cotton wool type material will give you an idea of the general area of the plant which is infested, but is not necessarily where the bugs are eating and lurking right now. The best way to find them is to use a magnifying lens.

If you use a small, powerful magnifying lens and examine the plant you may see the tiny bugs moving around on the leaves and stems. They look like small pinky-brown woodlice. You may also see their golden coloured eggs, which are often in the gaps between leaves and stems.

If you can find them you can remove them by dabbing and wiping away with cotton wool or small cotton bud soaked in alcohol such as ethanol. Thin tweezers are also helpful for getting into small crevices around the leaf and stem junctions. You will need to repeat your checks every couple of days for 2 – 3 weeks.

If a plant is badly affected, you may need to remove some or all of the leaves from the plant. Begin by removing the most severely damaged and mildew-covered leaves; this will make it easier to find any mealy bugs or their eggs. The plant should eventually grow new leaves. Be careful how you handle the possibly infested leaves: clean up carefully, and don’t contaminate other plants/pots/trays, etc.

Weevils

Adult weevils are not a big problem, except for eating chunks out of leaves. However, their larvae can cause horrendous damage to succulents and other plants. Pot plants are usually worst affected, but garden plants are also affected. The Weevils lay their eggs in the soil/compost and then the little white grubs eat the roots of the plants. They often tunnel into thick fleshy roots, completely hollowing out the inside of the roots. Eventually the plant falls over or comes away from the soil with little or no roots attached.

For many plants this root destruction can kill them, but the ability of succulents to easily grow new plants from leaf or stem cuttings means that once the infested roots (and any weevil grubs) are removed there is a good chance that the plant can either recover and grow new roots or be used to propagate new plants.

Be particularly careful when bringing plants inside from the garden, or when placing tender plants outside for the summer. Keeping plants off the ground (on a table or rack) will reduce the risk, and using lots of grit in the potting mix and topping with lots of grit may also help to deter them. Removing the potting mix and checking the roots before repotting with fresh compost/grit is probably a good idea for plants which have spent the summer in the borders or rockery.

There are chemicals or nematodes available to control weevils. If you find a weevil, dispatch it quickly.

Other pests

Aphids, scale insect, slugs and snails, thrips and some other insects can also be a problem at times.