Everything You Need To Know about Lavender Rhododendrons

Written by Brenda Woods Updated 11/18/2024

Brenda Woods

Brenda Woods is an accomplished writer and managing editor with more than two decades of publishing experience. She has spent over 10 years covering home services and home improvement projects. Brenda supports her team in evaluating dozens of home service providers, surveying and speaking to hom…

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Lavender rhododendrons are the go-to for any homeowner looking for a stunning specimen plant or lively hedge that provides year-round visual interest while requiring little maintenance. These drought- and pest-resistant rhododendrons have leathery green leaves year-round and grow fragrant, deep lilac blooms in spring. Their only real downside is their shallow root system, but a healthy dose of mulch can take care of that. Here’s everything you need to know about lavender rhododendrons.

Lavender Rhododendrons at a Glance

• Lilac blooms in clusters of eight to 10
• Fragrant blossoms
• Compact size perfect for smaller spaces
• Year-round visual interest
• Drought-tolerant
• Shallow root systems

Appearance of Lavender Rhododendrons

Lavender rhododendrons grow in a rounded shape. They have deep green leaves with a leathery look that keep their color year-round. In spring, deep lilac bell-shaped blooms emerge. Clusters consist of eight to 10 flowers each.

Lavender rhododendrons are compact, growing to 4–5 feet tall with a 4–5 foot spread.

Lavender Rhododendron Specifications

Hardiness Zones for Lavender Rhododendrons

USDA Hardiness Zones indicate the regions where plants can grow based on minimum winter temperatures. Lavender rhododendrons grow in Zones 5–8—across most of the country. They do not grow as far south as southern Texas or Florida.

Planting Lavender Rhododendrons

The best time to plant lavender rhododendrons is early spring or fall. We recommend taking these steps:

• Choose a sheltered planting site that receives full sun or partial shade.
• Clear away any turfgrass, debris, or weeds.
• Dig a hole that is the same depth as the root ball and twice as wide.
• Remove the lavender rhododendron from its container and place it in the center of the hole. You want its roots to be slightly below the soil level. If you plant them too deep, their shallow root systems may suffer from root rot.
• Begin backfilling the hole. Stop halfway and water deeply to settle the soil. Then, continue filling the hole.
• Apply a 2–3 inch layer of mulch around the root zone to preserve moisture, being careful not to touch the trunk.

Ideal Growing Conditions for Lavender Rhododendrons

Lavender rhododendrons are low-maintenance, highly adaptable to a wide range of soils, and able to grow under varying light conditions.

• Sun and Shade: Lavender rhododendrons can grow in full sun to partial shade. Plant them in full sun for the most robust flower growth or at least ensure they get six hours of direct, unfiltered sunlight per day.
• Soil: Lavender rhododendrons are highly adaptable to a wide range of soil conditions, with a preference for acidic, moist, organically rich, and well-draining soil. Well-draining is a required feature if you want to avoid root rot. If you have heavy clay soil, consider planting in a raised bed.
• Watering: Lavender rhododendrons require an average amount of water. Water them deeply once per week or slightly more often during summer dry spells. Do not water if the top 2 inches of the soil are already moist—you can test this by inserting your finger into the soil.
• Fertilizing: Feed your lavender rhododendron in early spring as the new buds start to emerge. Use a slow-release, nitrogen-rich fertilizer with an NPK value of 10-8-6. Read the package carefully—too much fertilizer could burn your lavender rhododendron.
• Pruning: Lavender rhododendrons do not require pruning unless you notice dead, damaged, or diseased branches. You should clip those any time you see them. However, if you just want to prune to maintain shape or reduce height, only prune in spring after flowering.

FAQ About Lavender Rhododendrons

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