Do green walls need a lot of maintenance?

Yes, a living green wall needs regular care. The plants grow in panels on the wall with very little soil, so they depend on a watering system that never stops and on someone checking it. A climber wall, where creepers grow up cables from a planter, needs much less. We design green walls, install them and come back to look after them.

• We visit a living wall once a month. We check the watering, feed the plants, trim them and replace any that fail. See what we do on a visit.
• Water is what kills a green wall. A blocked drip line or a stopped pump hurts the plants fast. See why green walls die.
• Some plants fail in the first months. Replacing them is a normal part of looking after the wall. See who replaces them.
• Most problems are decided at the design stage. Light, access and drainage matter as much as the plants. See what we check first.
• Want one, or worried about yours? WhatsApp us a photo and tell us what you have in mind.

A green wall looks great on handover day. Whether it still looks great a year later depends on how it was built and how it is looked after.

This post explains what a green wall needs, why some of them die, and what we check before one goes up.

Do green walls need a lot of maintenance?

It depends on the type of wall.

A living wall holds its plants in panels, pots or felt pockets fixed to the wall. This is the dense, carpet-like wall most people picture. The plants have very little soil, so they rely completely on the watering system. It needs regular care.

A climber wall, also called a green facade, grows from a planter at the base. Creepers climb cables or a steel mesh up the building. The plants have real soil to draw on, so they need watering and a trim, and they cope better when something goes wrong.

If you want the full living wall look, plan for its care from the start. If low upkeep matters more, ask us whether a climber wall would do the job.

Why do green walls die?

Most often, because the water stopped.

When we are called to a wall that is dying, the cause is usually the water. A drip line has blocked, a timer has failed or the pump has stopped.

A living wall holds very little water of its own. When a drip line blocks, a timer fails or the pump stops, the plants fed by that line dry out first. In Singapore's sun, a section can turn brown before anyone notices.

The other common causes are these.

• The wrong plant for the spot. A west-facing wall takes hard afternoon sun. A wall under a deep overhang gets almost none. Each needs different plants.
• Pests. Mealybugs and scale insects spread quickly through plants packed this close together.
• Visits that get skipped. A small fault caught early costs a few plants. The same fault found months later can cost a whole panel.

What do you do when you come to look after it?

We visit a living wall once a month, indoors or outdoors. We agree the schedule when we design the wall, and a wall in hard sun or strong wind may need us more often.

On each visit, we go through the same list.

1. Run the watering system and check every line is dripping.
2. Feed the plants. On most living walls the fertiliser goes in through the watering system, which the trade calls fertigation.
3. Trim back plants that are crowding their neighbours or covering the drip lines.
4. Check for pests and treat them early.
5. Replace any plant that has failed.
6. Clear the tray or drain at the base, so water runs away from the building.

Between our visits, it helps if someone on site takes a quick look at the wall now and then. A brown patch spotted early is a small repair. Found a month later, it can be a replanting job.

What happens if the watering stops?

Tell us straight away. The plants start to suffer quickly, so speed matters more than anything.

WhatsApp us a photo of the dry patch and tell us where the wall is. The photo shows us which part of the system has stopped.

We aim to be there within one working day.

On a large or high wall, we can fit a flow sensor that sends an alert when the water stops, so nobody has to spot the dry patch first.

Who replaces the plants that die?

We do, as part of looking after the wall. When we find a plant that has failed, we replace it.

Expect a few plants to fail in the first months while the wall settles in. After that, losses should be small and scattered. Patches of dead plants in one area usually point to a fault, most often the water. We fix the cause first, then replant.

Normal plant losses are covered by the monthly maintenance fee. Replacing plants after damage, or after a fault outside our maintenance, is quoted separately before we do it.

What do you check before a green wall goes up?

We start with a free site visit. We look at the light, the height, the exposure and what the structure can carry.

These are the questions we answer before we design anything.

• Can every part of the wall be reached safely? A wall that needs a boom lift for every visit costs more to look after.
• Where does the water go? Waterproofing behind the panels and a drain at the base keep the water in the planting and out of the building.
• Do the plants suit the light? Which way the wall faces decides which plants will last. An indoor wall needs special lighting built in.
• Is there water and power close by? The watering system needs both.

Waterproofing, drainage, the plants and the lighting are all part of what we design and install. Our green wall projects include The Interlace, Hort Park, 99 Clover and DTZ Chai Chee.

We also take over the care of green walls that someone else built. We visit first to check the watering system and the plants, then tell you what the wall needs.

What should I send you?

WhatsApp us a photo of the wall, or of the space where you want one. Tell us whether it is indoors or outdoors and roughly how big it is.

If the wall is still on paper, the drawings help too. From there we arrange the site visit.