Head Gardeners’ tips
December 2022

Leftover seed packets can be sorted through. Any out-of-date seeds can be put to one side and you can arrange what you’d like to keep by variety or sowing time. I recommend making a sowing calendar and an order list for next year to help you plan ahead.

I can’t stress enough how important it is to keep tools in excellent condition. Blunt blades on cutting tools can damage plants and you’re more likely to injure yourself using unsharpened tools. Check your secateurs by using them on a piece of paper. If you can’t make a clean cut, it’s time to sharpen them. This is easy to do, I recommend having a look for demonstrations on YouTube. I always sweep down my tools before putting them away as well. This is a brilliant habit to get into because it helps to keep the shed tidy and reduces the likelihood of weeds or pathogens spreading around the garden.

By December most deciduous trees and shrubs will have shed their leaves. I recommend collecting leaves where there is a significant build up to avoid smothering your herbaceous plants. These can be stored in a cage built using wooden posts and chicken wire. The leaves will rot down and turn into leaf mould which is a fantastic resource for the garden. Used as mulch, it will improve your soil and help encourage beneficial bacteria and fungi.

You might assume that December is a lacklustre month for flowers, but actually there are some incredible plants to look out for. Garrya (tassel bush) features long silvery catkins and Stachyurus (spiketail) flowers look like strings of pearls cascading from its branches. Hamamelis (witch hazel) also has stunning flowers and Sarcococca (sweet box) produces a wonderful winter scent. You might even be able to see some signs of spring as daffodil tips and hellebore flowers start to emerge.

Provided the ground isn’t frozen, you can plant trees and shrubs now while they’re dormant. You won’t see much happening above ground, but the roots will be growing, helping to get the plant off to a strong start next spring. Buying trees and shrubs in pots can be costly but you can save money by purchasing bare-root plants. These are often whips that have their roots wrapped in fabric (e.g. hessian) to keep them warm. The only downside is that you’ve got to plant these straight away or the roots can dry out.

If you are on a tighter budget, you can grow new plants by taking cuttings. Hardwood cuttings are easy to do and this is the perfect time of year to try. They can be grown-on and planted out in the following autumn. You can also divide herbaceous perennials. Any established plants with a fibrous root system, such as asters or ornamental grasses, can be lifted out of the ground and split carefully into two or three before replanting. This is a fantastic way to fill out existing beds and rejuvenate older plants.

While dormant, trees and shrubs can be pruned. Plants that are prone to bleeding, such as figs, should be pruned as soon as possible before their sap begins to rise in early spring. Some plants require routine pruning, such as wisterias, otherwise they become too wild. For other plants, first ask yourself whether they really require pruning. If so, start by focussing on the “three D’s” and remove any dead, diseased, and damaged stems. Work steadily and check your progress. You might be able to use your woody waste by making plant supports or pea sticks ready for the next growing season.

With cold winds blowing and darkness creeping in, it can be a challenge to venture outside. Despite the weather, December can be strikingly beautiful in the garden. On a frosty morning the skeletons of old herbaceous stems glisten in the sunlight and winter flowering plants can catch you by surprise with their wonderful scents. There is plenty to do at this time of year. Once you start gardening, you will appreciate the fruits of your hard labour and all of what mother nature has to offer.

Wishing you a happy festive season!