Gadenin日本語Get the appThe method: soak, then dry right out
There is only one correct way to water a haworthia, and frequency is the only variable. Water until it runs freely from the drainage holes, empty the saucer, and then give no more water at all until the compost is dry through the whole pot. Splashing a little water on every few days keeps the top inch damp and the roots below it dry, which is the exact opposite of what the plant wants.
Check for dryness by weight rather than by touch. Lift the pot when you have just watered and again a week later, and the difference is unmistakable once you have felt it twice. A wooden skewer pushed to the bottom of the pot and pulled out works too: if it comes out with compost clinging to it, wait.
Water into the compost, not over the plant. Water sitting in the center of a tight rosette on a cool evening is a common route to a rotted crown, especially in the dense, banded types where the leaves overlap closely.
Never leave the pot standing in a full saucer or an outer cover pot. Fifteen minutes is enough to draw water back up into the compost, and haworthia roots do not recover from long periods in standing water.
The seasonal pattern, which runs backwards
Most houseplants drink heavily in summer and little in winter. Haworthia does not. It grows in spring and autumn and rests in the heat of high summer, so its two thirsty seasons sit either side of the season when everyone expects to water most. Watering a resting plant on a hot week is the single most common way a healthy haworthia is killed.
Treat the figures below as a starting point and let the pot decide. A small plastic pot in a bright window dries in half the time of a large clay pot in the back of a room, and both may be correct.
| Season | Plant state | Rough interval | How to judge |
|---|---|---|---|
| Spring | Actively growing | Every 7 to 10 days | Water as soon as the pot is dry through |
| High summer, above 86F (30C) | Resting | Every 3 to 4 weeks, lightly | Enough to stop the roots shriveling, no more |
| Autumn | Actively growing | Every 7 to 10 days | The strongest growth of the year. Do not skimp |
| Winter, in a warm room | Slow growth | Every 2 to 3 weeks | Water in the morning so the pot is not cold and wet at night |
| Winter, in a cool room below 50F (10C) | Near dormant | Once a month at most | Keep it nearly dry until spring |
Watering through the summer rest
During a heatwave a haworthia effectively closes for business. The roots stop absorbing, and any water you add just sits in the compost at room temperature around inactive roots, which is precisely the condition that rots them. The plant is not thirsty, it is waiting.
It still needs a little, though, because completely bone-dry compost for two months will shrivel the fine feeding roots and cost you the first weeks of the autumn growing season. The compromise is a small drink, given in the evening when the pot has cooled, roughly every three to four weeks, using perhaps a quarter of what you would give in spring. Aim to dampen the compost rather than to soak it.
Watch the outer leaves rather than the calendar. Slight softening or a shallow dimple in the lowest leaves means the plant has used its reserves and can take that light drink. Firm, plump leaves at the height of summer mean leave it alone, however long it has been.
Overwatered or underwatered: telling them apart
The two problems look similar for about a week and then diverge completely, and the difference is easiest to read at the base of the plant rather than at the leaf tips. Underwatering shows first in the oldest, lowest leaves and works inward slowly. Overwatering shows at the point where the leaves join the stem and moves fast.
| Symptom | Too much water | Too little water |
|---|---|---|
| Which leaves change first | Lower leaves, right at the base | Outermost leaves, from the tips back |
| Feel of the affected leaf | Soft, translucent, wet under pressure | Wrinkled, thin, dry and papery |
| Color | Yellow going to brown, then black at the base | Dull gray-green, red-brown at the tips |
| Speed | Days | Weeks |
| What to do | Unpot at once, cut off rotted roots, dry out for a week | Water thoroughly. Leaves plump up within a few days |
Shriveled leaves on compost that is already wet mean the roots have gone and cannot take water up. That is an overwatering problem wearing an underwatering disguise, and adding more water makes it worse. Unpot and look.
Water quality, and what to keep a note of
Hard tap water leaves white deposits on the leaves and on the pot rim, which is cosmetic rather than harmful. Rainwater or water left standing overnight avoids it. Use water at room temperature: cold water straight from the tap on a warm root system checks growth for several days.
The single most useful record for a haworthia is a dated line each time you water, nothing more than the date. After a year you can see your real interval in each season instead of the one you think you keep, and you will usually find summer is far wetter than you intended. Note the room temperature alongside it during hot spells, and the pattern of the summer rest becomes obvious on paper long before it is obvious on the plant.