Tomorrow morning’s clocks are set back and it seems like the whole world of gardens and plants retreats into itself for the next couple months. But I have a collection of succulents in the greenhouse that I go and visit on the dankest, greyest days in the sure knowledge that they will delight and enliven me, firing a shot across winter’s bows.

These plants are from the desert, where there is little sun in summer and plenty of cold in winter. They are protected from rain and cold by the greenhouse. 

All succulents are able to withstand drought by storing moisture in their cellular structure. Many also keep their stomata – small holes in their leaves – closed during the day and only open them at night to transpire. 

Monty Don shares his tips for growing succulents. He admits that he finds joy in visiting his greenhouse on the greyest of days. Pictured: Monty with a selection of his aeoniums

This means that succulents can thrive in temperatures that are significantly different from day-to-night, which is problematic for many other plants.

They are an uncommon example of a plant that loves being on a south facing windowsill that can get really hot during daylight but cools dramatically at night.

There are many types of succulents, but the most popular is the aeoniums. They are native to Madeira and the Canary Islands, North Africa, where they form shrubs along rocky hillsides. 

ASK MONTY 

QAbout 22 years ago, I planted orange and lemon pips. One pip grew. It has grown well and produces sharp spikes. But, will it ever bear fruit?

Lesley Wilcocks, Wirral

AIt is unlikely that it will ever produce fruit if it hasn’t produced any fruit in 22 years. It can take up 15 years for lemons to bear fruit from seeds. Yours may never produce fruit. Even if they do, it is unlikely that the lemons will be very good.

Q There are roots growing out of the bottom of the large pot that my Salvia ‘Hot Lips’ is planted in. These roots can I be cut?

Susan Walker, Newport

AYou can, but this is an indication that it needs a bigger container. Remove the salvia from the existing pot, allowing any loose compost to fall away, and repot into a container that is about 2.5cm or so larger all round, using a general purpose peat-free compost – ideally with a little grit or perlite mixed in to improve drainage.

Q My 15-year-old red ‘Crimson Cloud’ hawthorn flowered profusely this year and then died. Is it possible to allow a winter clematis or a fungus to grow through it?

Lincolnshire, Honor Hadwick

A Yes, dead wood will provide support for clematis climbers. When a fruit tree such as a hawthorn flowers with extra vigour or out of season, it is often a sign it’s in real trouble and is desperately trying to produce seed in order to reproduce.

Monty Don, Weekend, Daily: Write to Monty Mail, 2 Derry Street, London W8 5TT or email monty.don@dailymail.co.uk. Please include your full name Address We regret Monty can’t reply Send letters personally

They are more or fewer dormant in the summer and winter, the driest season. They can be allowed to dry completely, but they will need water every week in spring, autumn, and throughout their growing seasons. They will receive all the water they require from rain if they are outside, even in the driest of summers.

Aeonium colours range from the deep purple of ‘Zwartkop’ or ‘Blood’ to the light green of ‘Maximus’. ‘Blushing Beauty’ has red-flushed leaves and ‘Sunburst’ is variegated with yellow and green stripes. 

A majority of varieties are branched with one rosette of leaves per stem, but A. tabuliforme produces a flat disc that can be grown horizontally or vertically.

Aeoniums are not frost hardy so cannot be left outside in winter but they can be quite cool and don’t mind a little shade. It’s normal if dark leaves start to turn green or the lower ones fall off in winter or summer; they will regain their beauty once they start to grow again.

Although the rosettes of leaves are floral-looking, aeoniums’ real, star-shaped flowers emerge on a long stem. 

These can last several months but are not good news for the plant as the supporting growth ceases to exist once the flowers have set seeds. This means that the plant is dead for a flat disc such as A. tabuliforme. However, the stem that carried the flowers will live on. 

The spent flowerhead can be removed from the main stem. The rest of the plant will grow normally.

Spring cuttings are the best way for aeoniums to be propagated. Cut off the young, slender growth flush with the main stem. 

These should be left to dry for a few days so that the cut ends can form calluses. Next, pot them in a very grity compost mixture with at most half of the stem above soil level.

At this year’s Chelsea Flower Show Cornish nursery Surreal Succulents launched what they call x Semponium ‘Sienna’, the first cross between an aeonium and a sempervivum, another type of succulent. 

As well as having vibrant russet and green colour, it is both hardier than any aeonium, down as far as -5°C, and much faster growing than a sempervivum. 

MONTY’S PLANT OF THE WEEK

VIBURNUM FARRERI

Monty chose V. farreri (pictured) as the plant of the week and explained that it shouldn't be pruned for the first few years

Monty chose V. farreri (pictured) as the plant of the week and explained that it shouldn’t be pruned for the first few years 

The pinkish-white flowers of this fragrant plant are now fully in bloom. They may occasionally produce red fruits. These flowers can reappear in mid-winter or spring.

V. farreri grows to about 3m tall and there are two variations on the basic form, ‘Candidissimum’, which has pure white flowers, and ‘Nanum’, a dwarf form that is good for smaller spaces but is more reluctant to flower. 

For the first few years, do not prune viburnums; instead, take a fifth of the oldest stems from the base and remove them immediately after flowering.  

THIS WEEK’S JOB

SOW BROAD VEGETABLES

Beans are often grown after a root crop, and before brassicas. Place the seeds in double rows of 45cm apart at 23 cm spacing. They will reach 30cm in height, then stop growing until February when the days begin to lengthen.