How often should I water my plants?
How to tell when a plant actually needs water, why deep infrequent watering beats daily sprinkling, and the signs of overwatering.
- Difficulty
- beginner
- Time
- 15 min
- Read
- 2 min
Short answer
Check the soil rather than the calendar — push a finger 5cm in, and water only if it's dry at that depth. Water deeply and less often to encourage deep roots. Overwatering kills more houseplants and container plants than drought does, and its symptoms look confusingly similar.
Watering advice given as a frequency is nearly always wrong, because it depends on the plant, the pot, the compost, the weather and the season. Checking the soil takes five seconds and is right every time.
Step by step
- Push a finger into the soil to about 5cm before watering anything.Dry at that depth means water. Damp means wait. This single habit prevents most watering problems.
- Water deeply enough that it runs from the bottom of a pot.A light sprinkle wets only the top and encourages shallow roots that dry out immediately.
- Water less often but more thoroughly.Deep roots find their own moisture. Daily light watering trains roots to stay at the surface.
- Water at the base of the plant, not over the leaves.Wet foliage encourages fungal disease, and much of the water evaporates before reaching the roots.
- Water in the early morning where you can.Less evaporation than midday and the foliage dries before nightfall, which reduces disease.
- Check containers much more often than beds, especially in summer.A pot in full sun can dry out in a day. Established plants in the ground rarely need watering at all in a normal British summer.
- Look for overwatering symptoms: yellowing lower leaves, soft stems, soil that stays wet, fungus gnats.Confusingly, an overwatered plant can wilt just like a dry one, because the roots have rotted and can't take up water.
- Mulch beds and containers to reduce how often you need to water at all.A 5cm mulch dramatically reduces evaporation from the surface.
Tips
- Grouping pots together raises humidity around them and slows drying.
- Terracotta is porous and dries far faster than plastic or glazed pots. Adjust accordingly rather than treating all pots alike.
- A saucer left permanently full of water rots roots. Empty it 30 minutes after watering.
- Newly planted things need watering even in wet weather for the first season — their roots haven't spread beyond the planting hole yet.
Common mistakes
- Watering on a schedule — Plant needs vary with weather, season, pot size and growth stage. Check the soil instead.
- Little and often — Trains shallow roots that can't cope with any dry spell.
- Watering over the leaves — Encourages fungal disease and wastes water to evaporation.
- Assuming a wilting plant needs water — Root rot from overwatering causes identical wilting. Check the soil before adding more.
Questions people ask
How do I know if I'm overwatering?
Soil that stays wet for days, yellowing lower leaves, soft or mushy stems at the base, and fungus gnats. An overwatered plant may also wilt, because rotted roots can't absorb water.
Do established garden plants need watering?
In a normal British summer, rarely. Newly planted things need watering for their first year; established plants in the ground have root systems that reach moisture you can't see.