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How to use a self-watering planter

Updated: October 2026

The pot is on the kitchen floor, the wick is still in a little bag, and the listing promised the plant would cope while you were out. A self-watering planter only works if the rope or the liner reaches both the compost and the reservoir. You refill the tank instead of flooding the surface. By the end you should know where the wick goes, what a dry phase means, and when a smell or a leak means stop. Rankings stay on the [self-watering planter comparison](/hub/plant-accessories/self-watering-planter). Products Compared did not run a grow trial. A qualifying purchase can earn us a commission at no extra cost to you.

The pot is on the kitchen floor, the wick is still in a little bag, and the listing promised the plant would cope while you were out.

Our top picks

WSMKSZ WSMKSZ 25 cm pots, set of 3

Best overall

WSMKSZ WSMKSZ 25 cm pots, set of 3
9.4/10about £25.99
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Lechuza Lechuza BALCONERA Color 80

Rank 2

Lechuza Lechuza BALCONERA Color 80
9.2/10about £45.87
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yarlung yarlung 12.7 cm pots, set of 6

Preis-Tipp

yarlung yarlung 12.7 cm pots, set of 6
8.6/10about £16.99
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On this page
  1. 1.Set the wick or the liner before you water
  2. 2.Fill the reservoir, not the compost
  3. 3.The first fortnight
  4. 4.When something is wrong

Set the wick or the liner before you water

Thread the rope through the hole before you add compost, then firm the mix around it so it cannot slip back down. A nested pot, such as the yarlung 12.7 cm six-pack, works differently. The inner pot stands on legs above the stored water, and you seat it so it is not perched on the float. The Yimomoyi basin does not clip, according to UK reviews, so you assemble it where the plant will live. The Lechuza BALCONERA Color 80 uses a liner and an indicator rather than one loose string. Lechuza’s planting note says the indicator should have dropped after two or three days. Herb species sit on the windowsill herb page. Window versus float is the buying guide.

Fill the reservoir, not the compost

Put water in the reservoir until the window, the float or the indicator shows full, then stop. The RHS hanging-basket trial found that soaking the compost surface washes fines and feed into the tank, and the store then smells. On the Lechuza, use the drain plug outdoors in rain. Indoors, a plug left open empties the tank onto the sill. Lechuza’s catalogue says fill to the maximum, then allow about 2–10 days after the minimum mark. That range is for Lechuza planters, not a 12 cm wick pot. GrowTropicals says let the reservoir run empty so air gets back into the compost, then refill. A seller line of 9–12 days on the WSMKSZ pots stays a seller line.
WSMKSZ WSMKSZ 25 cm pots, set of 3

Testsieger

WSMKSZ WSMKSZ 25 cm pots, set of 3
9.4/10about £25.99
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The first fortnight

Roots do not find the wick on day one. A stored UK review of the WSMKSZ pots describes light watering from the top while a jasmine’s roots grew down toward the tray. On that set, one UK review said the supplied string did not wet the plant at all. Reseat the rope higher in the compost before you decide the pot is faulty. What working looks like is ordinary: the reservoir falls over several days, and the compost is moist a finger’s depth down. If a yarlung float only moves when you shake it, believe the compost, not the marker. Succulents, cacti, snake plants and ZZ plants do not belong in this routine. That split is on the houseplant and succulent page. If you already planted one, stop refilling the tank.

When something is wrong

A sour smell means compost fines have been sitting in the tank. Empty it, rinse the reservoir, and refill with plain water. Do not pour more feed through the top. Mould on the surface, which one Skelang reviewer reported when the soil stayed wet, is the same problem. Let the reservoir empty. Yimomoyi UK reviews say the clear basin falls off when you move a full pot, so lift from underneath. WSMKSZ pots leak at a slight angle. A sticky float on the yarlung pots is common in the UK reviews: shake it, and do not keep topping up a tank that is already full. If rods on the trellis bed will not go in, stop and return it. Get a railing checked before you hang a wet trough.

Common questions

Do I water the compost or the reservoir?
Fill the reservoir. The wick or the liner is supposed to move that water into the compost. A light watering on the surface is only for the first few days, while roots grow down, as one UK reviewer did with a jasmine in a 25 cm pot. After that, soaking the top washes compost into the tank.
How do I know the wick is working?
The water level falls over a few days and the compost is moist below the surface. Lechuza’s planting note says the indicator should have dropped after two or three days. If the surface is dry and the tank is still full, pull the rope up so more of it sits in the mix. One Fayavoo reviewer did that by about 2.5 cm.
What is a dry phase?
A dry phase means you let the reservoir empty so air can enter the compost, then you refill. GrowTropicals gives that as the houseplant practice. Lechuza states about 2–10 days after the minimum mark on its own planters, and says a hot day can erase the pause on a BALCONERA. It does not mean you leave the whole plant dry for a month.
How often should I refill?
Refill when the window, float or indicator shows the store is low. There is no single interval. A UK Lechuza reviewer refilled wheatgrass every 4–5 days. A small 12 cm pot on a sunny sill can empty faster than an 80 cm trough with a 5 litre reservoir. Hot weather shortens whatever the seller printed.
Why does the tank smell?
The tank smells when compost fines and feed sit in the water and the store turns stale. The RHS trial links that to watering the surface instead of the reservoir. Empty the tank, rinse it, and refill with water. Let it run dry between fills so the compost gets air.

Related pages

Self-watering pots for a holiday

Self-watering planters

Best self-watering planter for sill, pot or trough

Self-watering planter: what to check before you buy

Self-watering pots for houseplants, not succulents

Self-watering herb planter for a kitchen windowsill

Sources

Public UK sources used for this comparison, plus the amazon.co.uk listing facts in the display file. Shelf prices and star lines are those UK figures, recorded for this page in October 2026. They are a snapshot, not a promise.

  1. RHS: holiday care for houseplants (retrieved 16 October 2026)
  2. RHS: watering hanging baskets trial (retrieved 16 October 2026)
  3. Garden Organic: make a self-watering container (retrieved 16 October 2026)
  4. Lechuza UK planters assortment catalogue (retrieved 16 October 2026)
  5. Lechuza balcony planter sheet (retrieved 16 October 2026)
  6. Homes & Gardens: what are self-watering planters (retrieved 16 October 2026)
  7. GrowTropicals: do self-watering pots work for houseplants (retrieved 16 October 2026)
  8. Consumer Rights Act 2015, section 22 (retrieved 16 October 2026)