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Herb spiral for a small patio

Updated: October 2026

Your patio is a few square metres, or the balcony sits under a freeholder’s load notice, and the product photo hides the scale line under a coil of leaves. Before you buy a compact steel spiral you need the footprint in centimetres, the empty weight in kilograms, and a clear view of wet compost, because none of the Relaxdays listings state a filled weight. This page sizes a herb spiral for a small patio or balcony. It does not rank the kits or teach bricklaying. Start from the [herb spiral comparison](/hub/plant-accessories/herb-spiral) when you move from space to the three listings.

Your patio is a few square metres, or the balcony sits under a freeholder’s load notice, and the product photo hides the scale line under a coil of leaves.

Our top picks

Relaxdays Relaxdays herb spiral, 43 cm, 3 sections

Best overall

Relaxdays Relaxdays herb spiral, 43 cm, 3 sections
6.4/10about £60.90
View offer
Relaxdays Relaxdays herb spiral, 30/60/90 cm rings

Best value

Relaxdays Relaxdays herb spiral, 30/60/90 cm rings
5.9/10about £47.90
View offer
Relaxdays Relaxdays herb spiral, 40/80/120 cm rings

Alternative

Relaxdays Relaxdays herb spiral, 40/80/120 cm rings
5.6/10about £51.90
View offer
On this page
  1. 1.What fits on the paving
  2. 2.Empty weight is not wet weight
  3. 3.Balcony, plastic and pots
  4. 4.Flats, roofs and a 20 cm height
  5. 5.When the space is the constraint

What fits on the paving

Compact on amazon.co.uk often means smaller than a three-metre lawn coil. The ninety-centimetre rings are a ninety by ninety centimetre square, twenty centimetres high. The larger set needs a metre-plus circle at the same wall height. The pyramid is about sixty-one by forty-one centimetres and forty-three centimetres tall. Measure, including door swing and a balcony exit. If only one footprint leaves a walking gap, the ninety-centimetre square is the smaller ring. Plantura warns that stone spirals can overload balconies. A B&Q URBNLIVING plastic spiral was about £16.99 and lists conflicting sizes, H36 by W50 by D43 cm against another line on the same page. Measure the box. It is outside the three scored listings.

Empty weight is not wet weight

Empty weights are about 4.4 kg for the ninety-centimetre rings, 6.43 kg for the larger rings, and 6.17 kg for the pyramid. That is steel only. Filled weight is not stated, and there is no single figure for saturated peat-free mix you can apply with confidence. Do not multiply the 127.23 litre field by a guessed density and call it a balcony limit. A filled bed is heavier than 4.4 kg, and heavier after rain, on one patch of slab. For a roof or balcony, check the structure and ask a chartered structural engineer or surveyor. On a ground patio, empty weight still matters when you lift the kit.
Relaxdays Relaxdays herb spiral, 43 cm, 3 sections

Testsieger

Relaxdays Relaxdays herb spiral, 43 cm, 3 sections
6.4/10about £60.90
View offer

Balcony, plastic and pots

Balconies favour loads you can divide. The B&Q plastic spiral near £17 lists about 1.3 kg empty, then contradicts its own dimensions, and it is not the Relaxdays family. Ordinary pots, each inside what you can lift, let rosemary have at least thirty centimetres of depth, which is the RHS suggestion, while thyme sits on a shelf. Steel rings can work on a sturdy ground-floor slab once drainage is confirmed and nobody has banned them. They are a harder case where a freeholder forbids fixed planters. Mint is easier to keep in one pot than in a ring on a railing. Read compact beside ninety by ninety by twenty centimetres as a footprint, not as height. Twenty centimetres is not a deep home for rosemary.

Flats, roofs and a 20 cm height

Flats and maisonettes sit outside the England householder allowances Planning Portal describes for decking on houses. A kit twenty centimetres high does not cancel a lease that forbids planters on a balustrade. A roof adds wind and load together, which is why the RHS points you to an engineer or surveyor. A shallow ring on existing paving is not a deck. A timber stage under it can meet the thirty-centimetre platform line. Listed curtilage still goes to the council. If you still need a dry crown for rosemary, a shallow ring on a small patio is the wrong tool. Use pots, or masonry at ground level. Do not answer that with a heavier fill on a suspended slab.

When the space is the constraint

If a clear ninety-centimetre square exists on solid ground, the smaller rings can sit there, and the wet weight is still unstated. If the gap is about sixty-one by forty-one centimetres, the pyramid is the footprint that fits. A metre-plus circle is the larger rings, not a small-space default. If the slab is suspended or rosemary must move indoors, use pots and ask a professional before a filled steel bed goes on a roof.

Common questions

Will a 90 cm herb spiral fit a small patio?
It fits if you have a clear ninety-centimetre square plus room to walk past it. Measure before you order. Compact on the listing does not mean tiny.
Can I put a steel ring or a brick coil on a balcony?
A steel kit may be acceptable on a sturdy balcony where the lease allows it and the load has been checked. A brick or stone coil belongs on the ground, not on a suspended structure.
How heavy is it once the compost is wet?
The listings do not state a filled weight. Treat any fill as significantly heavier than the 4.4 kg to 6.43 kg of steel, and heavier again after rain. For a roof, ask a chartered structural engineer or surveyor rather than guessing from the litre field.
Is the £16.99 plastic spiral small enough, and how big is it really?
B&Q’s URBNLIVING unit was about £16.99 and about 1.3 kg empty in the listing we checked, and it publishes conflicting dimensions. Verify with a tape. It is a different product class from the Relaxdays steel, and it is not one of the three scored listings.
Do flats follow the same planning rules as a house?
No. Flats and maisonettes sit outside the typical England householder allowances for raised platforms. A lease can add further limits. A twenty-centimetre kit does not cancel those.
When are ordinary pots the safer small-space choice?
When the load is uncertain, when rosemary needs about thirty centimetres of depth, or when you must move herbs indoors for winter. Pots divide the weight and the risk across containers you can lift.

Related pages

Herb spiral buying guide

Best herb spirals

How to plant a herb spiral

Herb spiral

Steel or brick herb spiral: rings or a masonry coil

Sources

Public UK sources used for this comparison. Shelf prices, stars and review counts are the amazon.co.uk figures captured for these three listings on 20 October 2026.

  1. RHS: herbs in containers (retrieved 20 October 2026)
  2. RHS: grow your own rosemary (retrieved 20 October 2026)
  3. RHS: growing herbs (retrieved 20 October 2026)
  4. British Beekeepers Association: building a herb spiral (retrieved 20 October 2026)
  5. Garden Organic A37: making a herb spiral (retrieved 20 October 2026)
  6. Planning Portal: decking and raised platforms (retrieved 20 October 2026)
  7. Consumer Rights Act 2015, section 22 (retrieved 20 October 2026)
  8. amazon.co.uk listings for the three herb spirals (retrieved 20 October 2026)