Caring for Lena Scotch Broom in Winter

Lena Scotch broom (Cytisus ‘Lena’) is a hardy flowering shrub that can withstand cold winters. With its bright yellow blooms in spring and vibrant green foliage, Lena Scotch broom is a standout plant in any landscape. While this plant is largely low maintenance, it does require some care during the winter months to ensure it survives the cold and re-blooms in spring.

Overwintering Lena Scotch Broom

Lena Scotch broom is winter hardy to USDA Zone 5. This means it can survive temperatures down to -20°F. As long as you are growing Lena Scotch broom in zones 5-9, it should have no trouble surviving normal winter conditions. Here are some tips for overwintering Lena Scotch broom:

• Provide well-drained soil. Wet soil during winter freezes can damage roots. Be sure to plant Lena Scotch broom in soil that drains readily. Amend clay soils with compost to improve drainage.

• Avoid fertilizing late in fall. Fertilizing too late encourages new growth that is more susceptible to frost damage. Discontinue fertilizer 6-8 weeks before your average first frost date.

• Mulch the base of the plant. Apply 2-4 inches of shredded bark, leaves, straw or other organic mulch around the base of the shrub in late fall. The mulch insulates the roots and prevents frost heaving.

• Prune after flowering. To avoid removing flower buds, prune Lena Scotch broom immediately after spring flowering. This pruning also helps shape the plant.

• Check for pest damage. During dormancy, inspect the branches for egg sacks or other signs of insect pests Prune out infested areas to prevent pest problems in spring

• Prevent heavy snow damage Scotch broom shrubs have an upright, arching form that can be damaged by heavy, wet snow Carefully knock off heavy snow to keep branches from splitting or breaking.

Watering Scotch Broom in Winter

Lena Scotch broom is quite drought tolerant when established. The only time it may need winter watering is during a prolonged drought or periods of unseasonably warm weather that may cause it to break dormancy too early. Symptoms that indicate winter watering may be needed include:

• Wilting, shriveling or browning of foliage

• Branch dieback

• Lack of new growth in early spring

Ideally, give Lena Scotch broom a thorough soaking before the ground freezes. This helps saturate the soil and provides the roots with moisture during winter. Additional winter water should be applied sparingly. Wait until spring growth resumes before fertilizing and pruning.

Protecting Lena Scotch Broom in Cold Climates

In very cold regions under zone 5, Lena Scotch broom will need some protection during extreme cold snaps. When temperatures plummet below -20°F, take these steps:

• Cover the shrub with a fabric frost blanket, burlap or pine branches. Secure the cover loosely, allowing air flow to prevent mold and rotting.

• Spray antidesiccant on the leaves. Antidesiccant forms a waxy coating that prevents moisture loss during freezing winds and sun. Apply when foliage is dry.

• Pack mulch around the base. Mound organic mulch 8-12 inches deep around the base of the shrub for insulation. Pull mulch away in spring.

• Avoid fertilizing or excessive pruning. Pruning stimulates new growth that is tender and easily damaged by cold. Fertilizing late encourages growth instead of hardening off for winter dormancy.

If temperatures rise above 40°F for several days, remove any coverings to prevent premature leaf out. It’s normal to see Lena Scotch broom defoliate in very cold winters. Don’t worry, it will leaf out again in spring!

Signs of Winter Damage

Despite being winter hardy, Lena Scotch broom can sustain some damage during extremely cold winters. Signs of winter injury include:

• Bronzed, dried foliage

• Dead, brittle twigs and branches

• Lack of spring growth or leaf out

• Dieback of stems and branches

• Discolored areas or lesions on the bark

Minor winter dieback of tips and small branches is normal. Simply prune out the damaged areas in early spring. Prevent winter injury by providing good drainage, ample water before ground freeze, and extra protection during extreme cold.

Spring Care After Winter

As temperatures warm in spring, uncover Lena Scotch broom and remove any extra winter mulch. Gently prune out dead or damaged areas with clean, disinfected pruners. Fertilize Scotch broom in early spring with a balanced, slow-release formula. This encourages lush, vibrant foliage and plenty of flowers.

The late spring blooms emerge on old wood, so avoid heavy pruning. Lightly shape and thin overcrowded areas if needed. Water regularly if rainfall is lacking and apply a fresh layer of mulch around the base. With proper care after winter, Lena Scotch broom will reward you with an abundance of golden yellow blooms in late spring!