The most common watering mistake indoors is treating it as a calendar task. A pot dries at a rate set by its size, its soil, the species, and the air around it — and in Canada that air changes dramatically between a heated winter and a humid summer.
Judge by dry-down, not by date
Two reliable signals tell you a pot is ready for water. The first is weight: lift the pot just after watering and again a few days later. A pot that has lost most of its water feels noticeably lighter. The second is the finger test — press a finger into the soil to the depth that matters for the species and feel whether it is dry.
Different plants want to dry to different depths before the next drink, which is why a single schedule across a collection rarely works.
Dry-down depth by species
| Species | Let it dry to | Note |
|---|---|---|
| Snake plant (Sansevieria) | Almost the whole pot | Stores water in its leaves; the slowest to need a refill. |
| Pothos (Epipremnum aureum) | Top third | Leaves soften slightly when thirsty, a useful early cue. |
| Monstera deliciosa | Top half | Prefers a clear dry interval between waterings. |
| Fiddle-leaf fig (Ficus lyrata) | Top third | Dislikes sitting wet; consistency matters more than volume. |
| Peace lily (Spathiphyllum) | Surface only | The thirstiest here; it will wilt visibly, then recover after water. |
The Canadian winter effect
From roughly November to March, forced-air and baseboard heating push indoor relative humidity down. Lower humidity and warm air speed evaporation from the soil surface and the leaves, so a pot that took ten days to dry in autumn may dry faster once the heat comes on — even though the plant is growing more slowly.
The practical response is not a fixed change but more frequent checking. Keep using the weight and finger tests; let the plant set the interval. Grouping plants together or keeping them away from direct heat vents reduces how harshly the dry air acts on them.
Watch the saucer. Tip out any water left standing in the saucer or cover-pot within an hour of watering. Roots left sitting in water are a more common cause of decline indoors than under-watering.
How to water, not just when
- Water until it runs from the drainage holes, which moistens the whole root ball rather than just the surface.
- Let it drain fully, then empty the saucer.
- Use room-temperature water; very cold tap water is a shock to tropical roots.
- If you use a cover-pot without drainage, water over a sink and return the plant once it has finished dripping.
Summer, when growth picks up
Through the warmer months most of these species grow actively and use water faster. Expect to water more often than in winter, but apply the same dry-down checks rather than simply watering on a set day. Plants moved to a brighter spot for summer will also dry more quickly.
References
- University of Minnesota Extension — Watering indoor plants
- Royal Horticultural Society — Watering houseplants
Last updated: June 3, 2026.