Catawba Rhododendron Plant Profile

Classic Shrub for the Shade Garden

Rhododendron behind rustic fence.

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Catawba rhododendron is a member of the heath family, making it a relative of such landscape plants as:

An even closer relative is the azalea, which also belongs to the Rhododendron genus. This multi-stemmed plant is grown mainly for its large clusters of lavender flowers. But a secondary feature worthy of consideration is its large, attractive, evergreen leaves, which are glossy and a dark green color.

Botanical Name Rhododendron catawbiense
Common Name Catawba rhododendron
Plant Type Broadleaf evergreen shrub
Mature Size Will stay 6 to 8 feet tall and 4 to 6 feet wide for many years but can eventually get larger
Sun Exposure Partial shade to full shade
Soil Type Fertile, well-drained
Soil pH Acidic
Bloom Time April to June
Flower Color Most commonly lavender-pink but does come in other colors
Hardiness Zones  4 to 8
Native Area Southeastern United States

How to Grow Catawba Rhododendron

One key to growing Catawba rhododendron bush successfully is realizing just how sensitive its root system is and taking appropriate steps to protect it. For example, the root system does not like to be exposed to heat, which is one reason why it should be grown in the shade.

But locating the plant in the shade is just the beginning of pampering its roots. You can't let the roots dry out, so Catawba rhododendron would not be an ideal plant to grow in regions prone to drought. On the other hand, Catawba rhododendron does not like having wet feet (which is likely to happen if you are trying to grow it in a clayey soil), so good drainage is essential. In ground with poor drainage, the plant can suffer from root rot.

Moreover, this bush has a shallow root system, meaning that its roots are easily damaged (for example, by weeding too vigorously around it and accidentally striking its roots with a shovel). Some of these concerns can be addressed by applying 3 inches of mulch around your Catawba rhododendron. A layer of mulch will:

  • Reduce the amount of heat that permeates down to the root system
  • Help retain moisture
  • Cut down on weed growth and furnish a protective buffer between you and the root system

Catawba rhododendron is attacked by many kinds of insect pests. Happily, hummingbirds also like it.

Prune your Catawba rhododendron just after it is done flowering. Tardy pruning could cause a reduction in flowers for next year. As always when pruning shrubs, start by pruning off dead or damaged branches. Next, trim off any branches that are sticking way up above the rest, thereby spoiling the overall shape of the bush. Yearly pruning will promote a more compact shape.

Light

Give Catawba rhododendron a little morning sun at the northern end of its range. At the southern end of its range, give it full shade.

Soil

Make sure that the soil for these shrubs drains well. If the soil does not currently drain well, amend the soil with organic matter.

Water

Catawba rhododendron has average water needs, but try to keep its soil evenly moist.

Fertilizer

Fertilize Catawba rhododendron in spring yearly by working compost into the soil.

Warning

All parts of this bush are poisonous, so do not allow small children around it since they may be tempted to nibble at its foliage or flowers.

Uses for Catawba Rhododendron Bushes

Catawba rhododendron, with its rounded habit, nice foliage, and colorful flowers, is impressive enough to function as a specimen plant in spring. Alternatively, mass several Catawba rhododendron shrubs together to create an attractive living privacy screen. Gardeners with a lot of shade in their landscapes will value Catawba rhododendron as a plant that tolerates almost full shade (a growing condition that many plants simply will not put up with). It is an ideal plant for woodland gardens, particularly those with excessive shade.

Catawba Rhododendron Cultivar for Moon Gardens

If you are seeking shrubs for moon gardens and wonder if there is a white-blooming Catawba rhododendron, you are in luck. A cultivar of this popular flowering shrub with white flowers is Rhododendron 'Catawbiense Album.' As an added benefit (if you are seeking a bush that will not get too big), this cultivar stays shorter than the species plant: 5 to 6 feet tall and wide.