Topiaries: Give your garden structure and interest

Photographs Kosie Jansen van Rensburg, Jeandri Streicher, Francois Oberholster, Conrad Judson and supplied

Topiaries are not only pleasing to look at, they also add structure, interest and focal points to a garden.

"The advantage of clipping plants into topiaries is that they work well in both formal and informal gardens. In a more formal garden, such as that of Marti Forster in Franschhoek www.news24.com/home/gardening/readergardens/reader-garden-vive-la-france-20220311, topiaries are the main element," explains Karin du Plessis, owner of landscaping business In & Outdoor Gardens.

"Even though the garden mainly consists of topiaries, the different shapes and shades of green still provide plenty of variety.

"In a more informal garden, topiaries add structure to mixed borders. And in winter, when gardens have been pruned to their bare bones and the trees are without leaves, these plants are still striking and beautiful." Karin says it is also essential that the shapes and size of the shrubs complement the architecture of the house and the size of the garden. "Topiaries suit modern homes as well as those with an old-world look.

In a large garden, there may be a garden room or section specifically set aside for topiaries, or they can be used throughout mixed borders. In smaller gardens they can serve as a focal point and provide structure to the beds in a smaller format." According to Karin, an entire garden can also be designed with a topiary theme, but she says it's best to use other plants with long, strappy leaves - such as agapanthus - in-between to soften the formal shapes."

There is a fine line between shapes that look natural and those that look forced, says Karin. "In my opinion, weird designs such as faces, animals and too many layers don't work. They are too far removed from a natural look." This privet (above) was trimmed to form a parterre, a formal bed with knee-high hedges shaped into a pattern.

Plant selection

When Karin considers plants for topiaries, she prefers those that can be easily pruned and don't need attention on a weekly basis.

As gardeners become more proficient, she is happy to suggest a greater variety that will need more dedication. "Plants with grey foliage and others in different shades of green can be used in a garden, provided they are not planted together.

Choose one type of plant for a group of ball-shaped shrubs and repeat it elsewhere," she says. "Variety makes the garden interesting, but repetition brings in a sense of tranquillity and orderliness."

With no formality, a garden tends to look like a messy fruit salad. - Karin

Karin's pruning tips

START SMALL

• Plant small shrubs so that you can manipulate them into the desired shape from the get-go. A large plant can be used if it is isolated and suitable for clipping into the required shape.

• Repeat one type of plant in groups or rows, preferably in uneven numbers. Then it will look like a more natural grouping from all sides and not like a row of plants.

• The distance between plants is determined by how quickly they grow, their growth habits and the look you're ultimately going for.

A group of slow-growing plants that need to form a tight shape should be planted closer together than a fast-growing plant such as dune crowberry.

SHAPES

• Keep it interesting by using different shapes. Ball shapes are popular but also consider spirals, columns, tortoise shapes and circular discs for a bit of variety.

• Tortoise shapes are easier on the eye and not as formal as ball shapes. Star jasmine works well for this purpose.

Push the plant's long stems into the ground using wire bent into a hairpin shape and prune regularly - the sides into the shape of the shell and the top into a convex shape.

• Prune the tips of cones, spirals and columns into a rounded shape, otherwise they'll look too hard and formal.

PRUNING

• Use the right equipment. A small battery-powered hedge trimmer is a good investment. A large pair of garden shears also works well; just make sure they are always sharp.

Pruning topiaries with ordinary secateurs is not recommended.

• Prune regularly so that the shrub stays in the desired shape and to prevent it from getting bare stems and woody growth at the bottom.

I start pruning as soon as the shrub is planted, unless it already has a naturally rounded shape; the slow-growing forest num-num is a good example of this and needs very little pruning.

• Prune more often in summer. The more you prune, the smaller the leaves and the sturdier and denser the shrub.

• View the plant from all sides. I walk around it and trim all over until the shape is symmetrical.

Perfect forms don't happen overnight; it takes time to master the art. Keep practising - the plant will grow back if you make a mistake!

Use wire mesh as a guide to help you prune neatly. Adjust the size of the wire as the shrub grows. As you become more proficient, the wire won't be as necessary.

For a softer look, cut the edges rounder rather than in a box shape.

• While pruning, place a tarpaulin under the shrub - this saves you a lot of time and effort as you don't have to pick up the trimmed leaves afterwards. Simply tip the trimmings onto the compost heap afterwards.

Choose a design

If you've always wanted topiary shapes in your garden, try one of these designs and choose plants that do well in your garden and area. "Buy plants in 4-5kg bags, not bigger," advises Karin (above). "Small plants are easier to manipulate.

With fast-growing plants such as star jasmine and dune crowberry, you will need two to three plants per metre; with Australian brush cherry and spekboom, five plants per metre is best, and for slow growers such as common myrtle and forest num-num, six to eight.

"If you choose a slow grower, your design will work out more expensive since you have to buy more plants to form the pattern within a reasonable time. But don't place the plants right on top of each other - they must have enough space in which to grow."

Design Karin du Plessis and Jeandri Streicher * Illustrations Jeandri Streicher

VEGETABLE GARDEN

This design will work in a small space. You could even copy just one of the four blocks. Plant your favourite vegetables and edible flowers in the different beds.

Hedges Rosemary (Rosmarinus officinalis ‘Tuscan Blue')

Vegetables

• Spinach

• Beetroot

• Leeks

• Red onions

• Celery

• Carrots

• Cabbage

• Kale

Edible flowers

• Nasturtium

• Pot marigold

• Pansy

• Snapdragon

• Sweet William

• Marigold

WATERWISE CIRCLE

Create this circle with hardy plants that need little water for a predominantly indigenous look. For the circle in the middle, choose one of the three plants you've used in the surrounding beds.

Hedges (choose one):

• Spekboom (Portulacaria afra)*

• Plumbago auriculata*

• Salt bush (Rhagodia hastata syn. Einadia hastata)

For the beds (from short to tall):

• Inner circle: wild garlic (Tulbaghia violacea)*

• Centre: agapanthus*

• Outer circle: gaura (Oenothera lindheimeri)

* indigenous

FOCAL POINT

The uniformity of this design with a focal point in the middle creates a tranquil effect. Consider a water feature or a pot with a topiary in it.

Hedges (choose one):

• Common myrtle (Myrtus communis)

• Dune crowberry (Searsia crenata)*

• Small-leaved boxwood (Buxus microphylla ‘Faulkner')

• Dwarf Australian brush cherry (Syzygium paniculatum ‘Globulum')

Focal point in each bed (choose one):

• Lemon

• Pomegranate

• Quince • Kumquat

Shrubs in-between (choose one to create a uniform look):

• Star jasmine (Trachelospermum jasminoides)

• French or Spanish lavender

• Euphorbia ‘Diamond Frost'

Here's how...

Follow Karin's steps for laying out a topiary pattern in your garden:

1 Start by covering the entire surface with Bidim geotextile or weed barrier fabric. Both products are porous and allow water to permeate. Keep the fabric in place by pushing hairpin-shaped pieces of wire through the cloth and hammering them into the ground.

2 Use agricultural lime or maize meal to mark out the pattern on the fabric, then cut out the shape.

3 Fold the fabric back slightly where you want to plant so you can dig a furrow. It is easier to position the plants in a furrow than in single holes. Add compost and bone meal to the furrow and space the plants evenly apart.

4 Water the plants well and fold the fabric back again until it is about 10cm away from the stems. If the fabric is too close to the stems, it makes it difficult to apply fertiliser and compost to the plants.

5 Cover the fabric with a layer (about 5cm) of peach pips or gravel (save a little to fill in where necessary). The finer the gravel, the more elegant the design will look but keep in mind that finer gravel is more expensive. I like 6mm stones as they're easier to walk on. Grey stones, rather than brown, are the perfect foil for green plants. Also, be guided by the style and colour of your home when choosing stones. White pebbles are impractical - they soon show the dirt.

6 Give the shrubs an initial boost with LAN and 2:3:2, but take care not to let the plants get scorched. Thereafter, an organic fertiliser such as Atlantic Fertiliser All Purpose or Bio Ocean is a good option. With the fabric so close to the base of the plants, it is more difficult to apply sufficient nutrients, so you need to do so more often. It is better to sprinkle fertiliser around the root area than to use liquid fertiliser as most of the latter will be absorbed by the fabric. Since the main purpose of topiary plants is not to bear flowers, it's not necessary to feed them with a nitrogen-rich fertiliser such as 10:1:5. Nitrogen (the first figure in the ratio) is needed for flower formation.

7 If you want to create the pattern over a larger area, repeat it as many times as needed.