There are many different types, and sizes of holly plants; they can be deciduous or evergreen. In landscape design hollies are very often used as specimen plants or as a screen. Care must be taken when fertilizing holly. In the first 3 to 4 years, they should be fertilized with a balanced fertilizer (8-8-8 or 10-10-10). Apply 1 tablespoon of fertilizer at the base of the plant per 1 foot of height of the shrub. This should be done in the months of March, May and July. Mature plants (5 years and over) should be fertilized once a year (in late fall) with a slow-release fertilizer for acid-loving plants.
Determine the amount of fertilizer that you need to apply to your young holly plant (plants that are 1 to 4 years old) by measuring the height of the plant. You will need 1 tablespoon of fertilizer for every foot of height. Example: a two foot high plant will require 2 tablespoons of fertilizer.
Measure out the amount of fertilizer required. If your bush is tall and you need more than a tablespoon of fertilizer, put the required amount in a disposable plastic cup.
Apply the fertilizer to the base of the plant by sprinkling it around the perimeter of the plant. Note: fertilizer can be placed on top of mulch if you have mulched your plants.
Water the base of the plant to dissolve and distribute the fertilizer. Fertilizing gives the plants the required nutrients to maintain their health and color. Young plants will be fertilized in this manner in the months of March, May and July.
Apply a slow-release fertilizer for acid-loving plants to mature holly plants (plants that are 5 years old and up) in late fall. Follow the manufacturer's directions on the label.