Gaultheria mucronata: growing & care

Gaultheria mucronata is an evergreen shrub that thrives in acidic soil. Its white bell-shaped flowers and colourful berries are a beautiful sight in winter.

The evergreen prickly heath (Gaultheria mucronata) brightens up autumn gardens with little white to red berries. However, there are a few things to bear in mind when planting and caring for Gaultheria mucronata.

Gaultheria mucronata: origin and characteristics

Gaultheria mucronata, also known as the prickly heath or pernettya plant, is a member of the heath family (Ericaceae). The botanical name of the plant is Gaultheria mucronata, but it is still sometimes referred to by its former name, Pernettya mucronata.

Prickly heath originally comes from the moorlands of southern Chile and Argentina. The evergreen shrub spreads with creeping, underground runners and produces small dark green, glossy leaves with spiny tips. A perennial, prickly heath grows to about one metre high and wide, and, from May to June, develops many white bell-like flowers.

The flowers of the prickly heath have long pistils in their centres, which grow into small berries in autumn. Depending on the variety, these berries can be white, pink, purple or red. Importantly, prickly heath is a dioecious plant, meaning that each plant is either male or female, and it only the female plants that develop the eye-catching berries. For the berries to develop, they need at least one male plant nearby to provide pollen.

Note: In botany, it is customary for the scientist who first discovers a new plant to name it. In the case of prickly heath, it was long assumed that Pernettya mucronata and Gaultheria mucronata were two closely related plants that did not belong to the same genus. However, more recent studies show that the two names describe the same plant. Gaultheria mucronata, discovered by the botanist Jean François Gaulthier, was the first valid name for the plant and is therefore the accepted one. However, in shops, you may still find the plant under its other name.

The most beautiful Gaultheria mucronata varieties

Shops tend to sell varieties of prickly heath that have similar growth, but different berry shapes and colours. The following varieties cover a wide range of colours:

• Gaultheria mucronata ‘Mulberry Wine’: This variety bears large, round, pink to dark pink berries.
• Gaultheria mucronata ‘Snow White’: As the name suggests, the slightly dented berries of this prickly heath variety are white.
• Gaultheria mucronata ‘Signal’: The berries of this variety can become bold crimson.

Where, when and how to plant prickly heath

Gaultheria mucronata belongs to the heath family and, like other moorland plants, grows best in moist and acidic soil. When planting prickly heath at home, make sure the layer below the topsoil is permeable to prevent waterlogging. If the pH of your garden soil is neutral or even alkaline, replace a generous portion of it with an acidic soil, like ericaceous compost.

A semi-shaded spot in the garden is ideal for prickly heath. However, if you are opting for potted gaultherias, do plant the shrubs outside in late spring – from April to May – to allow them to harden before the winter frosts.

Tip: You are unlikely to find Gaultheria mucronata in garden centres and shops before autumn, but tree or shrub nurseries may offer the plants year-round.

To plant prickly heath between May and August:

• Dig a hole at least twice the size of the root ball.
• Fill with ericaceous compost and mix well with existing soil.
• Create marshy conditions with plenty of water.
• Remove the gaultheria from its pot and loosen the root ball.
• Put the plant in the hole and fill it up with soil until firm. 
• Form a ridge of soil around the plant to gather water.
• Cover with mulch (e.g., bark).
• In the coming weeks, keep the soil moist until the plant has established its roots.

You can also plant Gaultheria mucronata in pots. For this, use an acidic soil, such as ericaceous compost, as a base and place a drainage layer at the bottom of the pot to help prevent waterlogging. Place the potted plant in a semi-shady spot and keep the soil sufficiently moist. Keep your plants in a cool, but frost-free location over winter.

Gaultheria mucronata care

Make sure that the soil around your prickly heath is always moist, as it grows naturally in marshland. Always use lime-free water, like rainwater, for watering, as the shrubs are very sensitive to lime.

Occasionally add peat or ericaceous compost to the surrounding soil, as gaultherias spread outwards along the ground, and benefit from nearby acidic soil.

Tip: There is no need to prune prickly heath. However, occasional pruning does encourage fruiting, and you will do no harm by removing unwanted shoots.

For long-term success, it is best to fertilise prickly heath once a year in spring. An acidic liquid fertiliser or slow-release fertiliser, such as our Plantura Hydrangea Food, is ideal. Such fertilisers acidify the soil and provide acidic-loving plants with essential nutrients for healthy growth.

Hydrangea Food, 1.5kg

(5/5)

• For beautiful hydrangeas with lush blooms in pots & flower beds
• Prevents common deficiency symptoms & supports healthy plant growth
• Long-lasting fertiliser that is free from animal products - child & pet friendly

£12.99

Shop now!

Overwintering: is Gaultheria mucronata hardy?

Young prickly heath needs protection from winter frost. You can protect it by covering the shrubs with fir branches. In severe frosts, add an additional layer of straw or leaves. After a few years, the plant will be winter hardy, and will withstand temperatures between -15 and -17°C, though severe frost will damage its fruit.

For potted Gaultheria mucronatas, however, you must overwinter the plants and protect them from frost. If possible, ensure the plant still receives light during this time. In spring, move the plants back to their shady garden spot, look out for frost, and protect them when necessary.

Is Gaultheria mucronata poisonous?

Prickly heath is slightly poisonous. Among other things, the plant contains the active ingredient andromedotoxin, which can cause nausea and dizziness. Keep pets and small children away from the plants. Fortunately, the plant’s prickly leaves make them uninviting.

It is a good idea to plant Gaultheria mucronata with other marshland plants. Blueberries have similar requirements to the gaultheria and also produce delicious berries. Read our article on growing blueberries to find out how to do it yourself.