Should I prune leggy canes?

Yes, you can tip prune the canes to encourage branching and a sturdier structure. Do this in the summer to manage height.

Do black raspberries need a trellis?

While they can grow without one, a trellis helps keep the canes upright and prevents them from sprawling. This makes harvesting much easier.

Black raspberry: leggy growth, causes and fixes

Check these first

Measure the hours of direct sunlight the plant receives.
Check your recent fertilization history.
Look for signs of competition from nearby weeds or plants.

Likely causes

Low Light Levels
Most likely
How to tell: The canes grow long, thin, and reach toward the nearest light source. The plant looks sparse and weak.
What to do: Relocate the plant to a spot with full, direct sun. If you cannot move it, prune back nearby branches that are casting shade.
Excessive Nitrogen
Possible
How to tell: The plant produces rapid, soft, and spindly growth. The canes are weak and struggle to support themselves.
What to do: Stop using high nitrogen fertilizers during the growing season. Switch to a balanced, slow release fertilizer applied only once in early spring.

Leggy growth in other plants

Find out what's wrong with your black raspberry

The list above covers the usual causes. Pocket Botanist looks at a photo of your actual plant and tells you the likely cause, how serious it is, and what to try first. Identification and a health check are free.

When to worry

Some elongation is normal during the rapid growth phase in spring. Worry if the canes are so weak they cannot stand upright on their own.

Stopping it coming back

Provide full sun and avoid overfeeding with nitrogen. Use a trellis to support the canes as they grow.

Black raspberry: leggy growth? Check yours with a photo

Every plant is a little different. Take a photo of your black raspberry and Pocket Botanist tells you which cause is most likely, how serious it is, and what to try first. A few checks a day are free. Save the plant and you get care reminders timed for it.

Get the app · Or check it from a photo now, free

Questions people ask

Should I prune leggy canes?: Yes, you can tip prune the canes to encourage branching and a sturdier structure. Do this in the summer to manage height.
Do black raspberries need a trellis?: While they can grow without one, a trellis helps keep the canes upright and prevents them from sprawling. This makes harvesting much easier.

Why are my black raspberry canes getting so leggy?