What base should my greenhouse sit on?

Best Greenhouse Base Ideas: How to Build a Strong Base for Any Greenhouse

Timber perimeter base · gravel interior · the most common DIY build

A greenhouse base improves stability, protects against freeze–thaw movement, and keeps the frame and panels out of standing water.

6 Greenhouse Base Types

Ordered roughly from easiest to hardest to build. Most backyard growers end up with one of the first two — or a combination of wood and gravel.

DIY FAVOURITE

1. Wooden base

Cost-effective and adaptable. Adjustable in height, so it forgives sloped or uneven ground, and it takes gravel or soil inside.

MOST DURABLE

2. Concrete base

The permanent option, and the one we would pick in high wind or heavy snow. Available as a full slab or a perimeter footing.

LONGEST LIFE

3. Stone base

Durable and good-looking — the choice for permanent garden structures and raised greenhouse designs.

CLEAN FLOOR

4. Tile or paving base

Paving stones or patio tiles give you a base and a finished floor in one, without pouring concrete.

BEST DRAINAGE

5. Gravel base

The most practical DIY base, and the best answer to a wet site. Usually built inside a timber or metal perimeter frame.

LOWEST COST

6. Soil base

The simplest and cheapest option: plant straight into native soil. Best for small or temporary installations.

Which base is best for you?

It comes down to four things: your climate, the size of the greenhouse, your budget, and whether this is permanent or a DIY build you might move.

DURABILITY

Concrete

Best wind resistance and the least movement over decades.

DIY BUILD

Wood or gravel

A timber perimeter filled with compacted gravel is the best all-round DIY base.

DRAINAGE

Gravel

Water passes straight through — no standing moisture, no mud.

APPEARANCE

Stone or tile

Worth the extra labour if the greenhouse sits in view of the house.

BUDGET

Soil or wood

Lowest cost to get growing this season, with the trade-offs above.

Before you decide, check five things on site: sun exposure, soil and drainage, climate, ground level, and your anchoring materials. Whatever base you choose, it must be level, square and securely anchored before the frame goes up.

Do you actually need a base?

A base is optional on every Planta greenhouse. Here is what it buys you.

WHAT'S INCLUDED

Galvanized steel legs

Every Planta greenhouse ships with legs that extend about one foot into the ground. They anchor the structure, but in colder regions they usually do not reach frost depth.

WHY ADD A BASE

Freeze–thaw protection

A base protects the structure from ground movement as soil freezes and thaws, improves wind and snow-load performance, and reduces long-term shifting or settling.

HOW LONG IT LASTS

Up to 70 years of frame

Our heavy-duty galvanized frames are rust- and dust-resistant and can last decades depending on soil conditions. A proper base is what protects that investment.

Owner tending peppers inside her greenhouse

Speak With a Specialist

If you're not sure which base your site needs, get in touch with River, our greenhouse specialist. She will help you review options and make an informed decision.

Call 1-877-669-1286

Available from Monday to Friday, 9am–5pm EST

Building a base on uneven ground or a slope

01

Use a raised or stepped perimeter base rather than regrading the whole site.
02

Level the base, not the entire yard — adjust height with timber, block, stone or gravel.
03

Compact the sub-base thoroughly and add landscape fabric under gravel.
04

Square the base by measuring both diagonals before any frame goes up.
05

Anchor securely, and size the base for the longest house you might extend to.

Common base questions

Does my greenhouse need a base at all?

No — a base is optional on every Planta greenhouse. The galvanized legs extend about a foot into the ground and will hold the structure on their own. A base is what protects it from freeze–thaw movement, improves wind and snow-load performance, and stops long-term settling.

What is the easiest base to build myself?

A timber perimeter filled with compacted gravel. It is the best all-round DIY base: adjustable in height so it forgives uneven ground, quick to build, and it drains well.

Which base is best in high wind or heavy snow?

Concrete. It gives the best wind resistance and the least movement over decades. You can pour a full slab or just a perimeter footing — the footing is cheaper and still lets you plant in the ground inside.

My site gets waterlogged. What should I use?

Gravel. Water passes straight through, so there is no standing moisture and no mud. Lay landscape fabric under the gravel and compact the sub-base thoroughly.

Can I build on a slope?

Yes. Use a raised or stepped perimeter base and level the base rather than regrading the whole yard — adjust the height with timber, block, stone or gravel.

How level and square does the base need to be?

Level and square before any frame goes up — measure both diagonals and adjust until they match. Building on an out-of-square base makes the frame and panels difficult to fit.

Can I plant directly in the ground with a base?

Yes, with a wooden, gravel or perimeter-footing base — all three leave the soil inside open. A full concrete slab does not, so choose a perimeter footing if in-ground beds matter to you.

Should I size the base for a longer greenhouse later?

Yes. Extensions come in 6.5 ft sections, and redoing the base work later costs far more than building it longer once. Size the base for the longest house you might extend to.