Marianne Binetti

The end of April means it’s time to pay attention to your rhododendrons

Rhododendron Windsong works well in the front yard of master gardener Stephen Johnson in University Place because it stays compact. Photo taken April 28, 2015.
Rhododendron Windsong works well in the front yard of master gardener Stephen Johnson in University Place because it stays compact. Photo taken April 28, 2015. News Tribune archive

Near the end of April the nurseries will be overflowing with color.

Bedding plants or annuals in bloom can be purchased now but may still need to be protected from the last of the cold nights. Some heat lovers such as tomatoes, coleus and basil should not be allowed outdoors after dark.

Cool-season bloomers such as snapdragons, alyssum, pansies and lobelia do not need nighttime curfews after hardening up for a few days on a covered porch or patio.

It is a busy time in the garden with planting, weeding and feeding. Treat yourself to a fresh pair of gardening gloves.

Mentally break your landscape into manageable, smaller sections and dig in by cleaning, weeding and planting one section at a time.

Q. When should I prune my rhododendrons? — D.W., Maple Valley

A. Pruning after blooming is the general rule of green thumb, so if you must prune a spring flowering shrub like a rhododendron, get snippy with it once all the flowers fade.

Keep in mind that some types of rhododendrons were meant to grow into trees. Keeping rhododendrons with large leaves shorter than 5 feet tall will be a frustrating experience for you and the plant.

Q. Are there any rhododendrons that will stay compact or dwarf?

A. Yes, the species Rhododendron yakusiminum are dwarf shrubs that are suitable for small spaces. Just ask for the furry “Yak” at your local nursery. The felt-like hairs on the back side of the leaves on Yak rhododendrons help them to resist root weevils, the night-feeding insects that like to make notches along the margins of rhododendron leaves.

Q. Do I have to cut off all the faded blooms once my rhododendron is done blooming? — K.P., Sumner

A. Nope. Removing the faded flowers will tidy up the shrub, but your rhododendron will still bloom and grow if you let the faded blooms dry on their own and fall from the shrub.

Q. Are there some shrubs that will flower even in the shade? I thought rhododendrons and azaleas were shade lovers, but mine get very little blooms. The leaves look good and the plants are growing, but they do not flower as well as those that grow in the sun. — S.L., Tacoma

A. If you want lots of flowers, then give both rhododendrons and azaleas semi-shade. At least half a day of sun promotes the most buds. In general, rhododendrons with larger leaves like more shade and rhododendrons with smaller leaves such as PJM and the Impeditum rhodies prefer more sun.

The early-blooming “Christmas Cheer” rhododendron is one example of an easy to find variety that is a dependable bloomer in shaded locations.

Consider shrubs with colorful foliage for dependable color in your darkest corners. Fastia japonica and Aucuba japonica ‘Variegata’ are two tropical-looking shade lovers that stay evergreen in protected locations.

Hydrangeas and camellias bloom in the shade but like rhododendrons they flower most abundantly with at least 4 hours of morning sun.

Reach Marianne Binetti through her website at binettigarden.com or write to her at P.O. Box 872, Enumclaw WA 98022.
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