Handy hacks for pruning

Pruning shrubs - When and what shrubs to prune in my garden in Yorkshire

Pruning shrubs is one of my favourite garden tasks because it ticks so many boxes. Pruning is just so satisfying because;

• You can encourage your shrub to grow well in the spot you’ve given it.

• It’s therapeutic; you’re caring for your prize plant, helping it not only to grow but to prosper

• It’s a year-round job. Some shrubs like a haircut in high summer and others like a bit of a trim in the winter

• Pruning means you’re going to chop-off twigs, stems and branches. All these can go in the shredder and make a great carbon-rich material (don’t worry - more on this later!) for rich and nourishing compost

• You can prune to form a neat and tidy shape - think balls and other geometric shapes - or to form more natural-looking

So pruning has its advantages. What do you need for pruning shrubs?

A trusty sharp pair of secateurs (see image), comfortable to hold and brightly-coloured.

(I’d be a rich man if I got a pound for every time I couldn’t remember where I’d put them!)

A pruning saw, for stems and branches thicker than 2cm (1 in) in diameter.

Loppers for pruning stems 1.5- 2cm (½ - 1 in) in diameter

Long-handled pole pruner for overhead stems and branches

(I find this gardening tool invaluable)

Shredder (chops up long stems and branches into chips, perfect for adding to heaps and bins to create rich and nutritious compost which your prize plants adore)

Big bag or trustee wheelbarrow for collecting twigs, stems and branches

Right, I’m all tooled up, what should I prune and when should I prune it?

There are two main looks I go for with pruning;

• Shrubs that make a neat and geometric shape (known as topiary in the gardening world)

• Shrubs that look good when they have an open structure and are more informal-looking

Shrubs that make a neat and geometric shape (known as topiary in the gardening world)

Some shrubs look great when they are pruned to a perfect round, made into a pyramid shape or even shaped into an animal. These shrubs form the backbone to the garden, they’re long-lasting, evergreen and create a strong framework for all the other flowers and plants in the garden.

How do I prune these shrubs?

Use a pair of shears to lightly trim the ends of the stem and keep stepping back to see the shape. If you’re happy, keep snipping the stems with your shears until the plant is at your desired height.

Perfect shrubs for neat shapes include:

Box (see image) - Buxus sempervirens

Privet - Ligustrum

Mexican orange blossom - Choisya ternata

Sweet box - Sarcococca confusa

Oleaster - Elaeagnus pungens

Pittosporum

Shrubs that look good when they have an open structure and are more informal-looking

Generally these shrubs are deciduous (lose their leaves in winter) for bare branches during the colder months. I find these shrubs look their best with branches at different lengths. They have a more relaxed look.

In the UK the general rule of thumb is to prune after your shrub has flowered. I would say this is the case for shrubs that flower at any time between January and August inclusive.

For any shrubs that are in flower at any point from September to the New Year, wait until the following April (or May in the north) to get your secateurs out.

10 shrubs that flower before September

Flowering currant (see image) - Ribes

Forsythia

Kerria japonica

Camellia

Flowering quince

Skimmia

Spiraea arguta

Rhododendron

Weigela

Broom - Cytisus

10 shrubs that flower at some point between September and the end of January

Butterfly bush (see image) - Buddleya davidii

Abelia grandiflora

St John’s wort - Hypericum

Fuchsias

Hebes

Cast oil plant - Fatsia

Hibiscus

Hydrangeas (paniculata group)

Mahonias

Shrubby cinquefoil - Potentilla

So it’s the right time of year for me to prune the shrubs that look good when airy. How do I prune these shrubs?

Follow these steps in order for on-going success. It’s what I adhere to when I’ve got hold of my secateurs.

1. Cut off any dead stems. They’re not doing much except over-crowding your plant. Not sure if the stem is dead? Scrape a small notch of wood off the surface of the stem; is it green underneath? Yes? Leave it- it’s alive. Is it brown and old? Yes? Snip it off - it’s dead.

2. Cut off stems that are growing into the centre of the shrub rather than growing outwards. Inward-growing stems tend to overcrowd the plant and stop oxygen-rich air passing through the plant. They also tend to rub against other stems which in the long run isn’t good.

3. Cut off about 1 in 5 stems right to the bottom to create a more open plant. Do this around the whole of the plant, not just in one spot. Take a step back. How’s it looking? It should look open, airy and have a balanced framework.

4. For a third of the remaining stems reduce the height by about a third to an outward- facing bud.

A what? An outward-facing bud?

When you look at a stem of a shrub or tree you’ll notice that more often than not the buds radiate around the stem in all different directions up the entire length. (see image)

Snip a stem just above a bud that’s facing in the direction away from the plant (i.e. an outward-facing bud)

The outward-facing bud will open up when your shrub has its next growth spurt. The bud will have the space to develop into a stem without the stem crashing into another one or any other obstacle like a wall or fence.

So why does pruning just above a bud mean that the bud will open out into a leaf or flower?

It’s all to do with hormones. I’m no scientist but I know there’s a concentration of growth hormones around buds that are called into action when there’s some degree of change to the plant (a severed stem- in the case of pruning).

It’s almost like a bud is dormant then it wakes up and has work to do.

Anything else I need to know?

Roses tend to die back a little bit when you prune them. Instead of pruning just above the bud go about 4-5cm (1 ½ -2in) further up the stem (or just under the next bud if closer) and then snip.

If you have individual rose bushes (i.e. are not climbing walls or on a trellis) cut stems back in November by about a third to a half so the bush stays well-anchored in the soil over winter. Basically you are reducing the height before winter when it tends to be windy.

Then in April or May cut back the stems to the next outward-facing bud. Just follow each stem down from the tip until you reach the next outward-facing stem. Cut the stem 4-5cm (1 ½ -2in) above this bud in case the stem dies back a bit as I mentioned above.