Rhododendron Not Blooming: Why Rhododendron Bushes Do Not Flower

Rhododendron Shrubs With No Flowers
rhododendron foliage
(Image credit: Antema)

Blooming rhododendrons look like colorful, puffy clouds floating through the landscape, so when they don't deliver, not only is it a huge disappointment, but a cause for concern for many gardeners. No blooms on rhododendrons is rarely caused by anything serious though, and with a little gardening know how, you can easily get a rhododendron to bloom. Read on to learn what can be done for a rhododendron not blooming.

When Rhododendron Bushes Do Not Flower

Like many plants in the landscape, rhododendrons have very specific needs that must be met before they will bloom freely. If your plant set buds, but didn't bloom, the buds were probably frost-nipped or destroyed by cold, drying winds. More commonly, however, buds aren't set at all, guaranteeing non-flowering rhododendrons the following spring. Among problems of rhododendron, not blooming is one of the easiest to cure. Here are the most common causes and some solutions: Not Enough Light. Although we commonly plant rhododendrons in the shade in North America in order to keep their feet cool, you've got to find a balance between shade and light. Not enough shade may overheat the plants, but not enough light and they'll lack the ability to produce the energy they need for blooming. Too Much Fertilizer. Feed your rhododendron all you like in the spring, but by late summer, you need to cut back on both fertilizer and water to give the plant just enough stress to encourage blooming. Always watch the amount of nitrogen you're giving your plant if it seems to be growing lots of new leaves without producing any flowers-- it's a sure sign you need to back off the feeding. Phosphorus, like bone meal, can help offset this. Age of Plant. If your rhododendron has never bloomed before, it may simply be too young. Every variety and species is a little different in this regard, so confer with your nursery workers and find out if the rhododendron you purchased is simply a late bloomer, so to speak. Bloom Pattern. Again, the species of your rhododendron matters! Some species simply don't bloom every year, or will bloom heavily one year and need another to rest before doing it again. If your rhododendron went to seed last season, that can also have an influence on blooms-- watch for next time and remove any dying blooms you find before they can become seed pods.

Kristi Waterworth

Kristi Waterworth was a regular contributor to Gardening Know How for many years, answering countless queries on plant pests and diseases.