A Review On How Fast Do Rhododendrons Grow

Table of Contents

Sharing is caring!

Last Updated on February 16, 2022 by

Let us review together how fast rhododendrons grow to learn if yours are growing at the right pace or not so we can know how to do it better.

Rhododendrons are highly popular due to the unique beauty of their brightly colored blossoms. Their flowers are available in shades of red and white, pink and purple, bringing out their bloom in the spring and summer months.

During winter, the many varieties do not produce flowers; instead, they have large green leaves.  The growth rate of rhododendrons dramatically depends on the type. For example, some varieties grow at a rate of less than an inch, while others grow as fast as 2 feet per year.

Additionally, blossoming happens much slower for plants started directly from seeds than from cuttings.

How Fast Do Rhododendrons Grow?

Check your plant and tell us do rhododendrons grow fast?  The growth rate of rhododendrons varies depending on the type you are growing.

Some varieties grow fast at about 2 feet per year, while others grow at an annual rate of about 0.5 inches.

How Fast Do Rhododendrons Grow

The American Rhododendron Society has an online database list that shows the plant height estimates after 10 years of growth on their website’s searchable database. Their list includes the following:

  • 44 cultivars that grow at a rate of 1 foot in 10 years
  • 164 cultivars that grow at 2 feet in 10 years
  • 366 cultivars growing at 3 feet in the same amount of time
  • 281 cultivars that grow at 4 feet within 10 years
  • 288 cultivars growing at 5 feet within the same 10 years

Most gardeners purchase rhododendron plants while in full bloom at the garden store or online. Although the seeds are available, most gardeners prefer to buy a plant instead of starting their seeds.  Starting them from seeds will take you at least 2 to 10 years for the first bloom to appear.

Growing a rhododendron from a cutting is possible; however, this method requires patience as well. Growing the roots can take as long as 3 to 4 months.  The best plant to go for is one that is in full bloom.

The Rhododendron Size Categories

As we have learned above, these flower’s growth rate varies depending on their type. Let’s look at different types and their growth rate.

  • 1 foot.  These miniature rhododendrons look like they are ground cover instead of bushes.
  • 3 feet.  These dwarf rhododendrons grow from 1 to 3 feet and are used as ornamental plants in flower and rock gardens.  They grow up to about 3 inches reaching their maximum height in 10 years.
The Rhododendron Size Categories
  • 6 feet.  These rhododendrons are the best to use as a hedge for privacy.  They grow as wide and tall, resulting in a similar look to a shrub and a tree.  It has an average growth of 6 to 8 inches each year, taking up to 10 years to reach full height.
  • Over 6 feet.  These are trees that grow up to 80 feet tall and are the broadest category.  Most of them are 8 to 10-foot range and can grow as much as a foot each year.  In 10 years, you will have obtained 10 feet or more.

The largest rhododendron is found in India and reaches a height of about 100 feet. You can find the largest rhododendron variety in the world growing in India.  It can reach heights of 100 feet.

Looking for Beautiful Flowers to Grow? Click Here:

How To Get Your Rhododendrons To Grow Fast

The first time you plant, you have no idea how big rhododendrons get, or maybe you have a slight idea. To get the best of your plant and make them grow fast, use the following tips.

  • Plant it in Suitable Soil.  Your soul must be rich and well-drained to allow water to flow freely so that the roots can get enough oxygen.  Ensure that your soil is acidic at 4 or 4.5 pH.
  • Water it Regularly.  Ensure your soil is moist enough and it needs to remain that way.  Water regularly, even if the weather is moist and humid. Don’t drown them but have the right amount of moisture to keep them growing faster and healthy.  Lack of adequate moisture stunts their growth.

Soil Plant Moisture Meter, 3-1 Soil Moisture pH Light Meter, Water Sensor for House Indoor Outdoor Plants

61uykvtws1L. AC SX569
  • Give it Enough Sun.  Ensure that your plant gets ample sunlight to help create large blooms and leaves.  Ample sunlight also keeps them healthy, allowing them to feed properly.  Remember, don’t give your plant open sunlight; instead, give it partial sun and shade.  You want the sun to help your plants by keeping them healthy but not frying them.
  • Plant Them in Deep Holes.  Even small rhododendrons require deep holes to give them proper room to grow and spread out. A deep hole helps them with long-term growth at a much faster rate.  With their roots having ample space to spread out, they will thrive and grow fast.

Read more about How Far Apart To Plant Azaleas

Rhododendron Types

Here are some popular rhododendron types you can choose from

  • Golden Lights: They require partial shade to full sun, medium moisture, planted on well-draining soil. They can handle extremely cold temperatures that are as low as -35ºF. Their blossoms start as red-orange buds open in early summer to reveal funnel-shaped orange flowers with ruffled edges.  The mature plants grow up to about 6 feet.
  • April Rose: This type requires partial shade to full sun, medium moisture, and well-draining soil.  These are cold-hardy plants that withstand low temperatures of as -25ºF.  April Rose is famous for its 2-inch wide, purple, funnel-like flowers.  The mature plants are 3 to 4 feet tall.

  • Nova Zembla: This variety requires partial sun and shade, medium moisture, and rich, well-draining soil. This type is low maintenance producing vibrant red blossoms in the middle of spring. Its mature plants mature at about 8 feet tall.


How big do rhododendrons grow?

Rhododendrons are among the first plants to bloom in spring, and they can reach heights of 6 feet or more.

When should I plant rhododendrons?

Rhododendrons are native to the mountainous regions of Asia. They can be found growing in areas as cold as -10°C (14°F) and as warm as +30°C (86°F). The plant is extremely hardy and can be grown successfully all over the world.

As such, Rhododendrons can be planted anytime after the soil has warmed up. They can tolerate shade, so you don't need to worry about full sun if you live in an area with lots of shade.

How quickly do rhododendrons grow?

They will certainly grow fast enough to out-compete other perennials if you don't do anything about it.

Rhododendrons are one of the most popular flowering shrubs, and one of the most popular garden plants. They’re a favorite for their ability to bloom in late spring, and for their ease of care. Most rhododendrons will grow from seed in about three years, but some may take as long as five years.

Rhododendrons can take 3 to 10 years to reach full size. They have large, leathery leaves and can be grown in containers, hanging baskets or ground beds. They’re often found in shady areas, but they can also be grown in full sun if you provide a moist environment.

It is difficult to tell how quickly Rhododendrons will grow. They may take several years before they flower. You might want to read up on the species you are interested in, and see if they are native to your area. If they are native, it might be best to stick with them for now.

They will certainly grow fast enough to out-compete other perennials if you don't do anything about it.

How can I make my rhododendron grow faster?

There are several things that can be done to help the rhododendron bloom more quickly.

These suggestions include: Provide ample amounts of fertilizer Remove weeds Keep the soil moist Water as needed Fertilize the plants The University of Minnesota also offers a free webinar about growing rhododendrons. You can view this video by clicking here.

Why is my new rhododendron plant not blooming?

Rhododendrons are very sensitive to cold temperatures and the soil should be kept warm (not too hot). Check for insects or disease that may be causing your plant’s problems. Try fertilizing, watering, or removing weeds. If you have an established rhododendron in a protected area, it may be time to move the plant outdoors to get more sun.

Final Thoughts

Rhododendrons are some of the most popular garden shrubs with their beautiful explosion of spring flowers. Additionally, they survive all seasons with rich deep-green leaves that add a pleasing color to your garden during winter and autumn.

Best of all, you can keep a spectacular garden filled with rhododendrons at low maintenance and cost.  Growing healthy and long-blooming plants start with rich amended soil that is well-draining at an ideal location.  The soil ensures your plant is well fed to thrive and produce intense blooms in its season.

Sharing is caring!