After You Prune Shrubs, Should You Fertilize?

Evergreen Shrubs

• Evergreen shrubs require pruning at different times, depending on the variety. The majority tolerate early spring pruning before the first new growth appears. The only exceptions are pines, which are best pruned right after growth shows but before new needle formation. Broadleaf evergreens, especially hedge varieties, tolerate pruning at any time from early spring until August. Fertilize evergreen shrubs following pruning only if you prune them in early spring. Shrubs pruned later in the season still require spring fertilization, but they do not need an application after later-season pruning

Deciduous Shrubs

• Leafy deciduous shrubs that do not flower need to be trimmed in early spring after the leaf buds begin to swell, but before they leaf out. The shrubs are still partially dormant at this time, so pruning will not shock them. Instead, this early season pruning helps encourage a fresh flush of growth once the buds begin to open. Apply the fertilizer a week or two after pruning once the new leaves begin to unfurl and the shrubs begin putting on active new growth. Some deciduous hedges require summer maintenance pruning, but they do not require a second fertilizer application.

Flowering Shrubs

• The pruning time for flowering shrub varieties depends on when the shrub flowers. The majority of these shrubs require pruning after they finish blooming, as earlier pruning removes the flower buds and diminishes the number of blooms. Fertilize flowering shrubs in early spring as they begin to bloom or leaf out. Since these plants are pruned later in the season, there is no need for a second post-pruning fertilizer application. The exceptions are shrub varieties that bloom multiple times through summer. These types sometimes benefit from a light midsummer fertilization to fuel the next flowering period.

Mature Shrubs

• Once shrubs reach maturity, they usually only need light annual pruning to maintain their size and shape. A mature shrub has reached its full size and has a 5- or 6-year-old root system that is fully established in the garden bed. While these shrubs still need some pruning, their fertilizer needs are minimal because annual fertilizer treatments only encourage more growth you must prune off. Do not fertilize mature shrubs after pruning unless the plant is suffering from a nutrient deficiency. Mature shrubs in lawn areas typically receive all their needed nutrients from fertilizer applied to the surrounding grass.