What Size Grow Tent Do I Need?

The right grow tent is the one that fits the space you have, holds the number of plants you want to grow, and leaves room above them for the light. Get those three right and everything else, the light, the fan and the filter, follows from the tent. This guide works through each in turn, then shows where the Budbox, Secret Jardin and AC Infinity ranges fit.

Start with the space, not the plants

Measure the room first: floor, height and the door you have to carry the tent through. Most full-size tents are 200 cm tall and need a little more than that to stand up (you assemble the frame, then lift the fabric over it). Leave 20 to 30 cm around the tent for the fan, ducting and getting the zips open, and remember the ducting has to go somewhere: a window, a loft, a chimney breast or a wall vent.

How many plants?

As a rule of thumb, plants in medium pots (8 to 12 litres) want about 40 × 40 cm of floor each once they are grown, so a 1 m² tent takes four to six of them. Larger pots (15 to 25 litres) grow bigger plants: two to four to the square metre. Small pots (3 to 6 litres) and a short vegetative period let you fit nine or more per square metre, the "many small plants" approach. Fabric pots, Air-Pots and Autopot systems change the shape of the plant but not the space it needs.

Fewer, bigger plants are easier to look after; more, smaller plants finish sooner. The tent makers' own suggestions (in the table below) assume medium to large pots.

Height: room for the light

A 200 cm tent does not give you 200 cm of plant. Take off the pot (25 to 30 cm), the light and its hangers (10 to 20 cm) and the gap the light needs above the canopy (30 to 45 cm for an LED bar fixture, 45 to 60 cm for a 600 W HPS). That leaves roughly 100 to 120 cm of plant, which is why the 140 to 160 cm tents are for seedlings, cuttings and short plants. Budbox Pro tents come in a standard and a taller HL height for this reason; Secret Jardin's DR150 and DR300 are 235 cm.

Tent sizes at a glance

Plant counts and lights are the ranges the tent makers print on their own pages, rounded together. See our LED wattage guide for choosing the light and the fan and filter guide for the extraction to go with it.

Where each range fits

Budbox Lite

Budbox Lite is the value range with the widest choice of sizes: 40 × 40 × 120 cm and 60 × 60 × 140 cm for seedlings and one or two plants, 80 × 80 × 160 cm, 100 × 100 × 200 cm (2 to 4 plants, 400 to 600 W), 120 × 120 cm in 180 or 200 cm heights (3 to 5 plants, 600 W), then 150 × 150, 120 × 240, 200 × 200, 240 × 240 and 300 × 300 cm. Quick-lock poles, one person can put it up. It is the tent in our grow tent kits.

Budbox Pro

Budbox Pro has the heavier frame (25 mm steel from the 120 cm size up), thicker fabric, bigger ports and a choice of Pro White or Silver lining, in standard and taller HL heights. The 75 × 75 cm comes in 100, 160 and 200 cm heights and is mostly used for mother plants or a separate veg chamber; the 100 × 100 takes up to a 400 W HID or the LED equivalent and four plants; the 120 × 120 up to 600 W and 4 to 6 plants; the 150 × 150 up to 1000 W and 6 to 9; the 120 × 240 two 600 W lights and 8 to 12 plants. Above that the Titan sizes: 200, 240 and 300 cm square.

Secret Jardin

Three ranges. Hydro Shoot is the entry level: HS60 (60 × 60 × 160 cm, for a 250 W light), HS80 (80 × 80 × 178 cm) and HS120 (120 × 120 × 200 cm, 30 kg roof). Dark Street is the mid range and comes with no pre-cut ports: you fit the intake and extraction brackets where they suit your room, which is handy in a tight space. DS60 is 60 × 60 × 158 cm, DS90 90 × 90 × 178 cm (a 400 W light) and DS120 120 × 120 × 198 cm (600 W). Dark Room is the premium tent: the DR150 is 150 × 150 × 235 cm for a single 1000 W light, the DR240 240 × 240 × 200 cm takes four 600 W or six 400 W lights, and the DR300 at 300 × 300 × 235 cm is the largest tent we sell (it ships on a pallet or is collected from the shop).

AC Infinity Cloudlab

Cloudlab tents run from the 422 (0.6 × 0.6 × 1.2 m) through the 844 (1.2 × 1.2 × 2 m) and 866 (1.5 × 1.5 × 2 m) to the 899 (2.4 × 2.4 × 2 m), and pair with AC Infinity's Cloudline fans and controllers. A propagation tent such as the Secret Jardin DP60 (60 × 40 × 60 cm) is light-tight, so it can share a room with flowering plants.

Lofts and attics

A loft has 200 cm of headroom in the middle and none at the eaves. The Budbox Pro Roof tents are shaped to match: the 120 × 120 cm has 140 cm side walls rising to 180 cm at the top, for a 400 or 600 W light and 4 to 6 plants; the 150 × 150 cm is the same shape for 6 to 9. Lofts are the hottest room in summer and the coldest in winter, so vent the extraction outside rather than into the loft, insulate the ducting and budget for a heater on winter nights.

Kit or separate parts?

A grow tent kit takes the guesswork out of matching the parts. Our 360 W LED kit is a Budbox Lite 100 × 100 × 200 cm with a Maxibright Varidrive 360 W LED, an Air EC fan, a Rhino Hobby 100 × 300 filter, five metres of 100 mm combi ducting and a timer; the 720 W kit does the same for a 120 × 120 cm tent with a Linx 720 W LED and a 125 mm filter; the 2 × 720 W kit (120 × 240 cm) and 4 × 720 W kit (240 × 240 cm) scale it up with 150 and 200 mm extraction. Buying separately makes sense when you already own part of the set-up, want a Pro tent or a particular light, or are fitting an awkward space.

Quick answers

What is the most popular grow tent size?

120 × 120 × 200 cm. It takes one 600 to 720 W light and four to six plants, fits a spare room or a large cupboard, and every fan, filter and light range has a size made for it.

What size tent do I need for two plants?

A 60 × 60 or 80 × 80 cm tent in medium pots; a 100 × 100 cm tent if you want them big. Check the height: a 140 or 160 cm tent suits short plants and cuttings.

More set-up guides

• Sizing an extraction fan and carbon filter
• LED grow light wattage by tent size
• LED or HPS? Why the best growers use both
• Hydroponics: systems, kits and how it works

Not sure what you need? Call the shop on 0117 971 3000 or pop in to the Bristol store and we'll help you pick.