Proper timing key to successful shrub transplants, experts advise

As the gardening season draws to a close, many home gardeners may be tempted to rearrange shrubs for a better landscape design — but experts caution that timing is key to ensuring healthy transplants.

Gardeners should avoid rushing to move late-blooming shrubs. For example, Clethra bushes, which flower in late summer, should be transplanted in spring — right after emerging from dormancy — to allow enough time for roots to establish before blooming begins. Conversely, spring and early summer bloomers are best moved in the fall, after their flowering season has ended.

Start with the roots
Before digging, it’s crucial to understand how deep and wide a shrub’s roots typically grow. Shallow-rooted plants like rhododendrons are easier to move than deep-rooted ones such as manzanita. The plant’s age also matters, as older shrubs have larger, tougher root systems.

When preparing the new site, the hole should be roughly twice as wide as the root system and the same depth as the plant’s original location. Always dig the new hole first to minimize the time the roots are exposed to air.

Gently tying branches together can prevent eye injuries and provide a clearer view while digging. Use a sharp shovel to carefully loosen soil around the plant’s perimeter, working gradually to lift as much of the rootball as possible.

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Planting with care
To move the shrub safely, place it on a tarp and drag it to its new location. Ensure the rootball sits at the same level as before — not too deep, to avoid rot, and not too shallow, to prevent drying and damage.

After positioning the plant, backfill the hole with soil, tamping it down periodically to remove air pockets. Water halfway through, continue filling, then water again before applying mulch over the root zone. Mulch helps retain moisture, regulate temperature, and suppress weeds.

Throughout the first year, water the shrub consistently until frost, but avoid fertilizing too soon. Experts recommend waiting until mid-to-late spring to apply a slow-release, low-nitrogen fertilizer — giving the plant time to recover and establish roots before promoting new growth.

Proper timing and technique, they say, can make the difference between a struggling transplant and a thriving shrub that flourishes for years.