Q.What Kind Of Food Should I Use On Rhododendrons? I’M IN ZONE 6.
I have one Rhdodendron that has brownish tips on the leaves and looks like something is eating some leaves. It blooms in the spring but does not look healthy after blooming.
Once established in soil with no nutrient deficiencies, rhododendrons usually can obtain sufficient nutrients for growth and flowering from the organic matter added to the planting hole and from the decaying 3-4" of mulch on the soil surface. A fertilizer ratio of around 6-2-1 applied at 2 pounds per 100 square feet to the soil surface is usually adequate. Holly-tone and cottonseed meal are also good fertilizers. But do not fertilize during hot summers or when the application date is less than three months before your average date of first frost. For Selah, the average date of first frost falls around the 1st-2nd week of October so stop fertilizing around the 1st-2nd week of July. Fertilizing after late June in a northern climate promotes tender growth in the fall, which doesn't harden off before the first frosts of winter. Continue researching why it "does not look healthy": not enough water; too much water; too much direct sunlight, etc.
