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Vertical Garden Calculator
Pocket count, saturated wall weight against your mount limit, and daily irrigation litres for a fabric, pipe, stacked or trellis vertical garden.
Vertical Garden Calculator
Chlorova · updated for 2026
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Saturated weights and daily water use are planning ranges for a media-filled system at field capacity, and real numbers swing with media blend, pot depth, sun exposure and wind, all of which can double a wall's thirst in midsummer. Load ratings describe the mount rather than the wall surface: a panel fixed to siding or a balcony rail is only as strong as its weakest fastener, and water weight arrives suddenly during irrigation rather than gradually. Check drainage every week, since a vertical garden that will not drain is a wall that will not stay clean, and most pocket systems dry unevenly across rows rather than evenly down the panel.
A vertical garden is a structural decision disguised as a planting decision, because media at field capacity weighs several pounds per pocket and the whole load hangs on fasteners that were rated for a picture frame. Water is the second half of that decision: a pocket wall in sun drinks far more often than the same plants in a bed, and a missed afternoon can finish a harvest. This calculator counts your pockets, converts them into saturated weight against the mount's rating, and tells you the daily litres the wall will ask for.
Sizing the Wall Before Building It
- Pick the system type you are actually installing.
- Choose the crop so water draw matches the planting.
- Count the rows of pockets on the finished panel.
- Count the pockets across each of those rows.
- Enter the rated load of the mount, not the wall.
- Read the saturated weight against the load percentage first.
- Trim rows until the verdict says comfortable.
- Hang the heaviest crops low, where a failure costs less.
- Use the weekly litres to size a drip line or timer.
- Re-check fasteners after the first full watering.
Pockets, Pounds and Litres
The grid is plain multiplication: rows times columns gives pockets, and a stacked tower doubles that into plants because each pocket carries two. Weight then comes from a per-pocket figure set by the system type, about 1.2 lb for a shallow fabric pocket and up to 4 lb for a pot hanging on a trellis, so a 24-pocket fabric wall saturates near 29 lb and a stacked tower of the same footprint approaches 72 lb.
Water is the other two-key table, a litre-per-pocket-per-day figure that varies with both the crop and the facing, since fabric dries fast with a small root zone and a pipe holds moisture around the roots. Load percentage is the safety number worth acting on: the saturated weight divided by the mount's rating, which is why the calculator prints the pocket count your mount actually allows rather than leaving you to divide it out in the garden.
Worked Example: A Balcony Fabric Wall
- You are hanging a fabric pocket panel with six rows of four.
- That prints 24 pockets, and 24 lettuce plants.
- Fabric pockets saturate near 1.2 lb apiece.
- So the full wall weighs about 28.8 lb at field capacity.
- Your railing bracket is rated for 60 lb of load.
- The share line reads 48% of the rating, comfortably mounted.
- Spare capacity says 31.2 lb, one more row of pockets.
- The mount would allow 50 pockets in total at that weight.
- Lettuce in fabric asks 0.15 L per pocket per day.
- Twenty-four pockets therefore drink 3.6 L daily.
- The week comes to roughly 25 litres on the wall.
- That litre count lands on the timer-and-drip verdict.
Weight and Water by System
The per-pocket figures behind the calculator. Saturated weight is media at field capacity inside the pocket, and daily water is the summer midpoint for the crop named, both of which rise with sun and wind exposure and fall under shade cloth or in cool weather.
| System | Saturated lb/pocket | Plants/pocket | Lettuce L/day | Tomato L/day |
|---|---|---|---|---|
| Fabric pocket | 1.2 | 1 | 0.15 | 0.30 |
| PVC pipe or gutter | 2.5 | 1 | 0.18 | 0.35 |
| Stacked tower | 3.0 | 2 | 0.30 | 0.55 |
| Trellis with pots | 4.0 | 1 | 0.20 | 0.45 |
Key Terms
- Field capacity
- The water a saturated media holds against drainage, the weight a wall carries.
- Rated load
- The maximum weight a fastener, bracket or rail is certified to hold.
- Pocket panel
- A vertical fabric or plastic sheet with planted geotextile pockets.
- Syringe watering
- A brief daily wetting that keeps a fast-draining wall alive between deep soaks.
- Drip manifold
- A distribution tube layout that feeds several pocket rows from one timer line.
Lessons From Walls That Came Down
- Fasteners fail at the peak of irrigation rather than the middle of a dry spell, so a mount at 90% of rating on paper is a mount that has no margin on the wettest day of the year.
- Fabric pockets dry unevenly, with the outer columns far thirstier than the middle, which is why a wall watered by hand usually needs two passes rather than one long soak.
- The crop that fails vertically is the fruiting one, because tomatoes get top-heavy in wind and their root zone is too shallow to buffer a hot afternoon on a sun-baked wall.
- Wind load and water load add together, and a tall panel on a balcony behaves like a sail in a storm, so anchor the bottom of the wall as deliberately as the top.
- A timer pays for itself in plants rather than water, since vertical crops are killed by one missed day and a twice-daily short cycle costs pennies.
Common Mistakes & Fixes
- Rating the panel and forgetting the bracket, screws and the wall behind them.
- Hanging tomatoes at eye level where wind and dryness both bite hardest.
- Watering once a day in August on a south-facing fabric wall.
- Assuming mint stays inside the pocket it was planted in.
- Skipping the saucer or drainage path and staining the wall below.
- Building a wall too tall to reach the top row without a ladder.
- Checking the anchors only after the first season of sway.
When to Use This (and When Not To)
Use it before buying a panel or drilling into anything, when the plan needs pocket count, load and irrigation sized together. For the planting layout on flat ground the plants-per-square-foot tool is the better fit, and the soaker-hose or drip-flow-rate calculators size the line feeding the wall once the litres are known.
Vertical Garden Calculator: Frequently Asked Questions
How much does a vertical garden weigh when wet?
Plan on roughly 1.2 lb per shallow fabric pocket and two to four lb per pocket for pipes, towers and pot-mounted trellises, so a 24-pocket wall carries 25 to 70 lb of saturated media. The mount's rating, not the panel's, is the number that decides whether it stays up.
Do vertical gardens need more water than beds?
They need it far more often, because a shallow root zone in a sun-baked pocket dries in hours rather than days. Total litres can be similar per plant, but the frequency is what pushes most growers onto a timer and a drip manifold.
What grows best in pocket planters?
Leaf lettuce, spinach, herbs and strawberries are the reliable crops, since they are light, shallow-rooted and cut-and-come-again. Fruiting crops like tomatoes work only low on the wall, where the weight is manageable and the reach is real.
Can I hang a pocket wall on a balcony railing?
Often yes, but the railing's own load rating governs rather than the panel's, and a railing built as a fall barrier is not the same as one rated for a hanging, waterlogged mass in wind. Bolt to a structural member or keep the wall short and light.
How many plants does a vertical panel hold?
One per pocket for fabric, pipe and trellis systems, and typically two for a stacked tower pocket, so a 6 by 4 grid gives 24 plants in fabric and 48 in a tower. Towers therefore ask for more water per pocket as well as more weight.
Should a vertical garden get morning or afternoon sun?
Morning sun with afternoon shade is the forgiving combination, because pocket media loses water fastest in hot afternoon light and shade buys you a whole missed watering. Full-sun walls are workable only with irrigation on a timer.
Sources & Further Reading
- Vertical Container Gardening: Water and Weight — University of Illinois Extension. Basis for pocket water use and irrigation frequency.
- Living Walls and Green Wall Systems — RHS Advisory. Source of the saturated-weight and mounting cautions.
- Container and Small-Space Vegetable Production — Kansas State Research and Extension. Supports the crop-choice and uneven-drying findings.
Chlorova Gardening Team
Builds, checks and documents every tool we publish
Chlorova editorial review
Checked against extension-service publications
Formula verified against published references · Updated