Self-watering pots: pros and cons
How reservoir pots work, and which plants like them
How they work
A self-watering pot has a water reservoir under the potting mix. A wick, or a column of mix, reaches down into the water and draws it up, keeping the mix evenly moist. You refill the reservoir through a tube or an opening at the side.
Instead of holes in the bottom, these pots have an overflow hole in the side, so extra water can escape.
What they're good for
Steady moisture suits plenty of plants and people.
- Plants that like to stay moist all year round.
- Vegetables and herbs in containers outdoors, which can dry out daily in summer.
- Saving water and nutrients, since little runs out of the pot.
- Leaving plants for a few days without worrying.
When to skip them
Plants that prefer drier soil, such as cacti and succulents, can rot when the mix never dries out. Citrus, which needs less water in winter, is a poor fit too. Give these an ordinary pot with drainage holes.
If a reservoir supplies more water than a plant uses, it can stay waterlogged and develop rot or gray mold. Then the plant needs a regular pot.
Tips for success
A few habits make these pots work well.
- Use a light potting mix, never garden soil, which is too dense and can drown roots.
- Start with moist mix and a full reservoir.
- Check the reservoir often; outdoors in hot summer weather it may need topping up daily. Clean it now and then to stop algae and disease.
- Keep the overflow hole clear so extra water can drain out.
- Water from the top once in a while to flush out fertilizer salts, and feed at the rate on the label or weaker.
A long-term choice
Self-watering pots work best as a plant's permanent home, where you can learn how fast it drinks. Repotting a plant into one just before a trip can do more harm than good, so set it up weeks ahead, or use a simpler holiday trick instead.
Related plant problems
Sources
- University of Maryland Extension: Self-Watering Containers
- RHS: Houseplants: holiday care
- University of Maryland Extension: Growing Media (Potting Soil) for Containers
- Virginia Cooperative Extension: Properly Watering Container Houseplants
General guidance, not a diagnosis. Written by PlantWiz in our own words from the sources above.