Conifers

How to Grow Conifers

Conifers are available in a wide variety of shapes and sizes, ranging from large specimen trees to cascading ground cover and fast-growing hedging plants. Most conifers are evergreen, providing valuable structure and colour to the garden, particularly during the darker winter months. With such a diverse selection to choose from, there is a conifer suitable for almost any soil type and garden situation. Here’s everything you need to know to grow them successfully.

What is a Conifer?

Conifers vary in size from large specimen trees to ground-cover plants and small varieties for rock gardens. They produce cones, ranging from the woody cones of pines to the fleshy, berry-like fruit of yews (Taxus).

Conifers are known for their foliage, which can be scale-like (e.g.pines) or needle-like (e.g. junipers), and comes in shades of green, gold, silver, or blue. Some varieties, like Cryptomeria japonica, also develop reddish hues in winter. Most conifers are evergreen, providing year-round structure, while some, such as European larch (Larix) and maidenhair tree (Ginkgo biloba), are deciduous, losing their leaves in winter.

Key Considerations for Growing Conifers:

Size & Shape: Conifers range from miniature plants (30cm) to towering trees (up to 100m). Be sure to choose one that fits your space. Check plant labels for mature size.

Growth Rate: Fast-growing conifers are ideal for hedging, but they require regular trimming. Slow-growing varieties can also grow large over time.

Foliage Colour: Conifers come in various colours, including green, blue, yellow, and variegated shades. Some, like Cryptomeria japonica ‘Elegans’, take on red hues in winter.

Evergreen vs Deciduous: Most conifers are evergreen, providing privacy and structure year-round. Some deciduous conifers, like the European larch, change appearance throughout the seasons.

Hedges: Conifers make excellent hedges, but consider growth rate and size to prevent overcrowding. Fast-growing varieties need regular care and won’t tolerate heavy pruning.

Native Conifers: In the British Isles, native conifers include common juniper (Juniperus communis), Scots pine (Pinus sylvestris), and yew (Taxus baccata).

Where to Plant

Most conifers prefer a sunny spot, but there are varieties suited to various conditions. Since conifers can live for many years and grow large, choose a location where they won’t cause problems in the future. Be mindful of planting near buildings or hedges, as overgrowth can lead to issues. Many smaller conifers are ideal for containers.

While most conifers are hardy, some, like Araucaria cunninghamii, are frost tender and need winter protection.

When to Plant

The best time to plant conifers is in late autumn (October-November) or early spring (March). You can also plant during autumn to early spring, as long as the soil isn’t waterlogged or frozen.

Container-grown conifers can be planted year-round, though avoid planting in hot, dry weather unless you're ready to water thoroughly. Bare-root conifers are available in late autumn and winter and should be planted as soon as possible after delivery.

How to Plant

If the soil is compacted, loosen it to help the roots spread. For heavy or sandy soils, improve structure by adding organic matter, like garden compost.

Most conifers don’t require staking, as they rely on wind movement to strengthen their stems and roots. However, large specimens should be staked for initial support. Planting carefully ensures your conifer thrives for years to come.

Ongoing Care

Once established, most conifers require minimal attention.

Watering

For the first two years after planting, ensure new conifers are regularly watered to keep the soil moist, especially during dry or hot spells. Once established, most conifers can manage without additional watering, except during extended droughts or heatwaves. Conifers in containers will need consistent watering, even in dry winter periods.

Feeding

Most conifers do well without extra feeding. However, for best results, you can apply a general-purpose granular fertiliser in late winter, following the recommended rate on the packet. Conifers in containers should be fed with liquid fertiliser from early spring to late summer.

Weeding

Grass and weeds compete with young conifers for water and nutrients during the first five years after planting. If planting a conifer in a lawn, leave a circle at least 90cm (3ft) in diameter without turf to reduce competition for moisture and nutrients, helping the conifer establish and grow properly.

Mulching

It's beneficial to apply a mulch of well-rotted manure, garden compost, bark chippings, or leafmould around the base of all conifers, especially newly planted ones. Mulch helps suppress weeds, conserve moisture, improve soil conditions, and provide nutrients.

Apply mulch when the ground is damp, ideally in late winter after fertiliser application, but it can be done any time between autumn and late spring. Be sure not to place the mulch directly against the stems, as this may cause rot.

Looking after Conifers in Containers

Conifers in containers need regular watering and feeding, and should be repotted into larger containers every 2-3 years as they grow.

Pruning and Training

Specimen conifers generally require minimal pruning. If necessary, prune conifers between April and the end of August to avoid browning of the foliage, which is more likely if pruned at other times. Most conifers won't regenerate from brown, dead wood if pruned into, with notable exceptions being yew and, to a lesser extent, Thuja.

You can manage the size of conifers by trimming and pruning.

• Trim the green foliage similarly to a hedge, ensuring a clean, leafy finish, but avoid cutting into old brown wood.
• If a conifer becomes too tall, remove the growing tip to limit further upward growth, with only a few wispy shoots remaining that can be easily trimmed.
• If conifers grow too large for their space, replacing them is often the best solution.