How to grow dwarf willows

Choosing a dwarf willow

Dwarf willows grow well in a wide range of sites, although they really thrive in full sun and free-draining soil. These ground-huggers are particularly useful in exposed, cold situations. They are also popular choices for rock gardens and large containers, and the spreading forms make handy ground cover.

There are several species and cultivars of dwarf willow to choose from, depending on how much space you have and where you want to grow them:

• For rock gardens, troughs and containers – popular options include the netleaf willow (Salix reticulata)at only 7.5cm (3in) tall and 30cm (1ft) wide; S. ‘Boydii’ at up to 30cm (1ft) high and wide; Swiss willow (S. helvetica) at 60cm (2ft) tall and 40cm (16in) wide
• For ground cover on banks or to fill large bare gaps – Salix nakamurana var. yezoalpina has an indefinite spread and is only 15cm (6in) high; S. repens spreads to at least 1.5m (5ft) wide and 60cm (2ft) tall

Always check the eventual spread of dwarf willows before buying. Even tiny plants may be wide spreading, so make sure you have enough space for future growth.

To browse the range of dwarf willows and track down specific cultivars, go to RHS Find a Plant. You can filter your search by height and spread, growing conditions and RHS Award of Garden Merit.

Around 20 Salix species and cultivars have an RHS Award of Garden Merit, which shows they performed well in RHS trials, so are reliable choices.

You may also be able to visit the UK National Willow Collection at Rothamstead Research (Harpenden in Hertfordshire), to see the wide range of species it grows.

How and what to buy

Dwarf willows are available all year round, but are easier to find in spring in garden centres, shrub nurseries and online by mail order.

How to choose healthy plants

Buying: trees and shrubs

When to plant

Autumn through to spring is the best time to plant dwarf willows.

If you buy and plant in autumn, these young, small shrubs can begin to establish their roots over winter and will need less watering than if you plant in spring.

However, willows are often more easily available in spring. In this case, plant them straight away and water regularly over the first summer, especially in dry spells, to help them settle in and prevent them drying out.

Where to plant

In borders and rock gardens

• Plant in full sun and very free-draining gritty soil
• Allow spreading forms plenty of space – check the eventual spread before buying
• These tough, fully hardy shrubs are ideal for exposed, windy, cold locations

Rock gardens: plants

Rock gardening

In troughs, sinks and containers

• Use an equal-parts mix of a loam-based compost
  

  Can refer to either home-made garden compost or seed/potting compost:

  
  • Garden compost is a soil improver made from decomposed plant waste, usually in a compost bin or heap. It is added to soil to improve its fertility, structure and water-holding capacity. Seed or potting composts are used for growing seedlings or plants in containers - a wide range of commercially produced peat-free composts are available, made from a mix of various ingredients, such as loam, composted bark, coir and sand, although you can mix your own.

  , such as peat-free John Innes No. 2 and coarse grit for good drainage
• Water well after planting, and in hot, dry spells until plants are established

Sink and trough gardening: plants for

Sink and trough gardening

How to plant

Dwarf willows are quick and easy to plant, and should be planted as soon as possible after buying – see our planting guides below.

How to plant a shrub

Watering

• Water newly planted dwarf willows regularly for the first two or three summers, especially in hot, dry spells
• To avoid unnecessary watering, check if the soil feels dry at a depth of about 15cm (6in), and if so, water generously, allowing it to soak in well
• Once well established, dwarf willows shouldn’t need additional watering
• Plants in containers should be checked daily during hot, dry spells as the compost
  

  Can refer to either home-made garden compost or seed/potting compost:

  
  • Garden compost is a soil improver made from decomposed plant waste, usually in a compost bin or heap. It is added to soil to improve its fertility, structure and water-holding capacity. Seed or potting composts are used for growing seedlings or plants in containers - a wide range of commercially produced peat-free composts are available, made from a mix of various ingredients, such as loam, composted bark, coir and sand, although you can mix your own.

  will dry out faster. Containers will need less water in winter but should still be checked occasionally

Collecting, storing and reusing water

Watering

Feeding

Dwarf willows growing in borders shouldn't need feeding unless they are showing signs of nutrient deficiencies.

Dwarf willows in containers will benefit from the addition of controlled-release fertiliser when planting, repotting or top-dresing.

Container maintenance

How to feed plants

Nutrient deficiencies

Caring for older plants

Once dwarf willows have settled in, they need very little attention or maintenance. Just check they are getting enough water in summer, and remove any weeds.

You can prune dwarf willows occasionally in spring, after the catkins have faded, but little pruning is generally needed. You could remove some of the oldest stems, to maintain a balance between young stems (some with winter colour) and older stems with catkins.

Shrubs and trees: light pruning

Hardwood cuttings

Dwarf willows are easy to grow from hardwood cuttings

Hardwood cuttings are taken from mid-autumn until late winter from vigorous healthy shoots of the current year's growth - this will be woody but pliable. Use for deciduous climbers, shrubs, trees (including fruit) and some evergreens such as hollies.

, between November and January – see our guide below.

With willows in particular:

• Select healthy, woody stems from the current year’s growth, about pencil thickness and 20–30cm (8–12in) long
• Insert into deep containers filled with a 50:50 mix of peat-free multi-purpose compost
  

  Can refer to either home-made garden compost or seed/potting compost:

  
  • Garden compost is a soil improver made from decomposed plant waste, usually in a compost bin or heap. It is added to soil to improve its fertility, structure and water-holding capacity. Seed or potting composts are used for growing seedlings or plants in containers - a wide range of commercially produced peat-free composts are available, made from a mix of various ingredients, such as loam, composted bark, coir and sand, although you can mix your own.

  and coarse grit
• Keep in a coldframe or cool greenhouse over winter
• Check from time to time to make sure they haven’t dried out or are sitting in soggy compost
• New shoots will appear from the buds in spring
• They should be ready to plant out in autumn

Cuttings: hardwood

Dwarf willows are usually robust, vigorous and healthy shrubs, if grown in a sunny position in soil that doesn't dry out. They don't grow well in chalky soil.

However, there are a few problems to look out for:

• willow anthracnose, scab and canker
• honey fungus
• tree rusts
• large willow bark aphids
• willow leaf beetles
• scale insects
• caterpillars and sawflies
• slugs and snails, which may damage soft, young, leafy growth
• ants can be a nuisance in well-drained soil and containers
• vine weevils can damage roots, especially in troughs, sinks and other containers

If you’re a member of the RHS, you can use our online Gardening Advice Service, via MyRHS, for any questions or gardening problems.

Managing pests and diseases without chemicals

Preventing pest and disease problems