Mature size & growth rate

How big does Zamia Palm (Macrozamia riedlei) get?

Also called Zamia Palm, Riedlei Macrozamia, Western Australian Cycad.

More about zamia palm

About Zamia Palm

Macrozamia riedlei · also called Zamia Palm, Riedlei Macrozamia · tropical

Zamia Palm is the most widespread cycad of south-western Western Australia, found in kwongan heathland, jarrah, and marri forest. It forms a low, stemless crown of stiff blue-green fronds, superb for Mediterranean-climate gardens and drought-tolerant planting schemes. Extremely drought-hardy but requires excellent drainage. Severely toxic to animals and humans.

Mature size: 0.5–1.2 m tall; fronds to 1.5 m long; very slow-growing over decades

Indoor size vs how big it gets in the wild

Zamia Palm is a tree at heart. Indoors a pot and your ceiling keep it to 0.5–1.2 m tall, but in the ground it is a different scale of plant entirely (fronds to 1.5 m long; very slow-growing over decades). Indoors and in a pot, expect 0.5–1.2 m tall. In the ground with no restriction it is a completely different plant — fronds to 1.5 m long; very slow-growing over decades — which is why the pot, the light and the pruning matter so much for the size you actually end up with.

It gains real height on a trunk or main stem, adding a tier of leaves a year and eventually reaching for the ceiling — this is a plant you grow up, not out.

Growth rate and years to mature

Zamia Palm is a slow grower. Realistically, expect a decade or more — slow growers like this add only a few centimetres a year, so expect 8-15+ years to reach their indoor ceiling. Its feeding profile backs this up: fertilise sparingly — native to low-nutrient soils and sensitive to excess phosphorus, which is toxic to many western australian plants. use a low-phosphorus, slow-release native plant food or cycad fertiliser once in autumn. avoid high-nitrogen or high-phosphorus fertilisers entirely.

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

How to keep zamia palm smaller

You are not stuck with the maximum size. For zamia palm specifically, these are the levers, in order of impact:

The decisive tool is the secateurs: zamia palm can be topped (cut the main growing tip) to cap its height and force a bushier, shorter shape.
Keeping it deliberately pot-bound in a snug container slows the whole plant and limits ultimate size.
Prune in spring so it heals fast; remove the tallest leader back to a node to reset the height.
Good news: slow growth means topping it once buys you years before it needs doing again.

The keep-it-smaller method, step by step

Pick the new height. Decide how tall you want zamia palm and find a leaf node or branch point just below that.
Top the main stem. Cut the main growing tip cleanly just above that node in spring; this permanently caps the height and forces side branches.
Keep the pot snug. Avoid jumping to a much bigger pot — a slightly restricted rootball keeps the whole plant smaller.
Maintain the shape. Prune back the tallest new leaders each spring to hold it at the height you chose.

How to grow zamia palm bigger or faster

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

It already wants the bright light it needs; warmth, a yearly pot-up and spring-summer feed are the accelerators.
Pot up a size every year or two while young; restricted roots are the main thing holding height back.
Feed regularly through the growing season and keep it warm — height comes from sustained good conditions.

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

When zamia palm outgrows the room (or the pot)

"Too big" usually arrives as one of these signs for zamia palm:

The top leaves pressing against or bent by the ceiling — the classic "this is now too tall indoors" sign.
It has to be moved away from a light source it has literally outgrown.
Roots filling the largest pot you can reasonably keep indoors — at that point it is top-or-prune or move it outside (if hardy).

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

Zamia Palm size — frequently asked questions

How big does zamia palm get?

Zamia Palm reaches 0.5–1.2 m tall when grown indoors, and far larger where it grows unrestricted (fronds to 1.5 m long; very slow-growing over decades). It gains real height on a trunk or main stem, adding a tier of leaves a year and eventually reaching for the ceiling — this is a plant you grow up, not out.

Is zamia palm slow or fast growing?

Zamia Palm is a slow grower. Expect a decade or more — slow growers like this add only a few centimetres a year, so expect 8-15+ years to reach their indoor ceiling. Zamia Palm is a tree at heart. Indoors a pot and your ceiling keep it to 0.5–1.2 m tall, but in the ground it is a different scale of plant entirely (fronds to 1.5 m long; very slow-growing over decades).

How long does zamia palm take to reach full size?

Roughly a decade or more — slow growers like this add only a few centimetres a year, so expect 8-15+ years to reach their indoor ceiling. Light, pot size and feeding move that timeline more than anything else.

How do I keep zamia palm smaller?

The decisive tool is the secateurs: zamia palm can be topped (cut the main growing tip) to cap its height and force a bushier, shorter shape. Keeping it deliberately pot-bound in a snug container slows the whole plant and limits ultimate size. Prune in spring so it heals fast; remove the tallest leader back to a node to reset the height. Good news: slow growth means topping it once buys you years before it needs doing again.

How can I make zamia palm grow bigger or faster?

It already wants the bright light it needs; warmth, a yearly pot-up and spring-summer feed are the accelerators. Pot up a size every year or two while young; restricted roots are the main thing holding height back. Feed regularly through the growing season and keep it warm — height comes from sustained good conditions.