Mature size & growth rate

How big does Thornless Evergreen Blackberry (Rubus laciniatus 'Thornless Evergreen') get?

Also called thornless evergreen blackberry, cutleaf blackberry.

More about thornless evergreen blackberry

About Thornless Evergreen Blackberry

Rubus laciniatus 'Thornless Evergreen' · also called thornless evergreen blackberry, cutleaf blackberry · edible

'Thornless Evergreen' is a vigorous, semi-evergreen blackberry with deeply cut leaves and long, thornless canes that crop heavily in late summer. Productive and easy to harvest, it yields firm, flavourful berries that freeze well, holds its foliage in mild winters, and trains neatly along wires or fences for the home grower.

Mature size: Canes 2-4.5 m long, trained to 1.5-2 m on wires; spreads via tip-rooting and suckers.

Watch for — Grey mould and fruit rot: Botrytis ruins ripe berries in wet, congested growth. Space and tie canes for airflow and pick fruit as it ripens.

Indoor size vs how big it gets in the wild

Thornless Evergreen Blackberry reaches its full size within one growing season — there is no "long-term" size, just how big it gets before you harvest or it dies back. Indoors and in a pot, expect canes 2-4.5 m long, trained to 1.5-2 m on wires. In the ground with no restriction it is a completely different plant — spreads via tip-rooting and suckers. — which is why the pot, the light and the pruning matter so much for the size you actually end up with.

It sizes up fast and once, racing from seedling to full size in a single season; after cropping it is finished, so size is a within-season question.

Growth rate and years to mature

Thornless Evergreen Blackberry is a fast grower. Realistically, expect a single growing season — it reaches full size in one year, then is done. Its feeding profile backs this up: apply a balanced fertiliser or well-rotted manure in early spring and mulch with compost. a potassium feed as berries form aids cropping. avoid late-season nitrogen, which produces lush, frost-tender growth at the expense of fruiting wood.

Want this turned into the right next pot at the right moment? The pot size calculator and the thornless evergreen blackberry repotting guide cover when and how much to size up — pot size is one of the biggest levers on how fast thornless evergreen blackberry grows.

How to keep thornless evergreen blackberry smaller

You are not stuck with the maximum size. For thornless evergreen blackberry specifically, these are the levers, in order of impact:

Choose a compact or dwarf variety of thornless evergreen blackberry from the start — that is the most reliable size control for an annual.
Grow it in a smaller container to naturally limit how large it gets.
For some crops, pinching or pruning the growing tips keeps the plant shorter and bushier.
Sow a little later or space plants closer if you specifically want smaller individual plants.

How to grow thornless evergreen blackberry bigger or faster

If you want it to fill the space sooner, push the conditions rather than hoping — for thornless evergreen blackberry the accelerators are:

Full sun, warm soil and steady water are what drive a crop to full size fastest.
Sow at the right time for your zone so it gets the whole season to size up.
Feed appropriately for the crop and never let it check (stall) from drought or cold.

Light is almost always the ceiling. The thornless evergreen blackberry light requirements page covers exactly how bright a spot it needs to grow at its potential instead of stalling.

When thornless evergreen blackberry outgrows the room (or the pot)

"Too big" usually arrives as one of these signs for thornless evergreen blackberry:

It sprawls beyond its bed or container before harvest — usually a spacing or support issue.
It flops or needs staking once it hits full height.
Once it has fruited or bolted, it is at its final size for good — the next plant is a new sowing.

If it is the pot rather than the room, it is a repotting job, not a goodbye — see the thornless evergreen blackberry repotting guide. If you want more of this plant instead of a bigger one, the thornless evergreen blackberry propagation guide turns prunings into new plants.

Thornless Evergreen Blackberry size — frequently asked questions

How big does thornless evergreen blackberry get?

Thornless Evergreen Blackberry reaches canes 2-4.5 m long, trained to 1.5-2 m on wires when grown indoors, and far larger where it grows unrestricted (spreads via tip-rooting and suckers.). It sizes up fast and once, racing from seedling to full size in a single season; after cropping it is finished, so size is a within-season question.

Is thornless evergreen blackberry slow or fast growing?

Thornless Evergreen Blackberry is a fast grower. Expect a single growing season — it reaches full size in one year, then is done. Thornless Evergreen Blackberry reaches its full size within one growing season — there is no "long-term" size, just how big it gets before you harvest or it dies back.

How long does thornless evergreen blackberry take to reach full size?

Roughly a single growing season — it reaches full size in one year, then is done. Light, pot size and feeding move that timeline more than anything else.

How do I keep thornless evergreen blackberry smaller?

Choose a compact or dwarf variety of thornless evergreen blackberry from the start — that is the most reliable size control for an annual. Grow it in a smaller container to naturally limit how large it gets. For some crops, pinching or pruning the growing tips keeps the plant shorter and bushier. Sow a little later or space plants closer if you specifically want smaller individual plants.

How can I make thornless evergreen blackberry grow bigger or faster?

Full sun, warm soil and steady water are what drive a crop to full size fastest. Sow at the right time for your zone so it gets the whole season to size up. Feed appropriately for the crop and never let it check (stall) from drought or cold.