benefit from an annual application of fertilizer in spring or early summer (March through
June). Slow release (WIN - Water Insoluble Nitrogen) or organic
nitrogen is a better choice than quick release nitrogen since it feeds a
shrub more gradually and reduces the chance of fertilizer "burn."
Don't fertilize shrubs in
the midwest or northeastern US after July 4th since it may encourage a late
"flush" of new growth that might not get "hardened off"
before winter cold. It's best to apply granular fertilizers around the base
of a shrub without putting any in contact with the foliage or the trunk.
Liquid fertilizer is
different than granular products, with label recommendations often calling
for applying it over the foliage for additional uptake of nutrients through
the leaves. Early morning is a better time than the heat of the day for
these sorts of applications.
Always read and follow
fertilizer label instructions. More fertilizer is not necessarily better
since many fertilizers have a high "salt index" which increases their "burn"
potential on plants. It is always a good idea to water fertilizer into the
soil following an application. If you use wood mulch regularly it is a good
idea to use nitrogen fertilizer annually to help offset what the breakdown
of wood mulch robs from the soil.