Vertical Gardening

Irrigation design, overwhelmingly. Water runs down — so a single irrigation line feeding an entire wall over-waters the bottom and starves the top, which is exactly the pattern you see on failed walls: green at the top for a while, dead at the bottom, then dead everywhere. The fix is zoned irrigation with separate control at different heights. The second cause is plant selection that ignores aspect: a west-facing facade in a Kolkata May is an extreme environment, and much of what gets specified for green walls simply will not survive it. Both are design failures, not maintenance failures.

Enough that it is a structural question rather than a horticultural one, and it must be calculated saturated — not dry. Media, plants, water and structure together impose a real load on the building, and the load is highest exactly when the system is working properly. We provide the saturated weight calculation with the design, and it needs checking against the building’s structural capacity by someone qualified before anything gets fixed to the wall. Anyone selling you a green wall without raising this is skipping a step you cannot skip.

More than people expect, and this is worth being honest about before you commit. Irrigation needs checking regularly — a blocked emitter kills a zone within days in summer. Plants need replacing as they fail. Media needs periodic attention. Filters clog. The maintenance requirement does not go away, and a wall without a maintenance plan becomes a brown wall within a year or two. If nobody is going to maintain it, do not build it.

On terraces and rooftops, yes — trough and container systems work well for leafy greens, herbs and some vegetables, and they multiply growing area per square metre substantially. On a vertical facade, it is harder: media volume per plant is small, access for harvesting is awkward, and the aspect often is not right for productive cropping. Vertical food production works best on horizontal-ish systems stacked vertically, rather than on genuinely vertical walls.

It depends entirely on aspect, height and exposure, and honest answers here are shorter than the plant lists people hope for. North and east aspects support a considerably wider palette than south and west. Upper storeys get more wind and more sun than the base of the same wall, so the palette can differ within one installation. We would rather assess your specific wall and give you a realistic palette than hand you a catalogue list that photographs well and dies in May.