Alocasia Care Calendar: What to Do in Each Season

The year at a glance

An alocasia grows hard in the warm half of the year and does very little in the cold half. That split governs everything. Repotting, dividing, sprouting corms, feeding and hard cleaning all belong in the growing half, and the winter job is simply to keep the corm sound until the room warms again.

The dates on a calendar matter less than the temperature in the room. Judge the change of season by when the overnight temperature at the plant crosses about 59F (15C), not by the month.

Feeding in winter is the single most damaging thing you can do to an alocasia. A plant that is not growing cannot take up fertilizer, so the salts stay in the compost around the corm and burn the roots.

Spring is when the work happens

As the room warms past about 64F (18C) and the light strengthens, the corm starts moving and the plant can recover from being disturbed. This is the window for everything that involves the pot: repotting, separating offsets, sprouting the loose corms you find, and replacing collapsed compost.

Start feeding only once you can see a new leaf actually emerging, not on a date. Use a balanced houseplant feed at half the strength on the label, and give it after watering rather than to dry compost. A plant coming out of dormancy also needs the watering interval shortened gradually rather than all at once, because it has fewer roots than it had in autumn.

1. Wait for the first new leaf A dormant plant that has been dry all winter should get a little more water as the room warms, but no feed and no repotting until a shoot is visible. Feeding a corm that has not woken simply loads the compost with salts.
2. Do the repot before growth is fast Repotting just as growth restarts is ideal. The plant has a full season ahead of it and the disturbance costs it almost nothing.
3. Clean the leaves once Wipe or rinse both surfaces of every leaf as the season starts. It removes the mites that overwintered and lets the leaf work properly again.

Summer is the growing season

This is when the plant produces its biggest leaves, uses the most water and needs the most attention. Water use can double compared with spring, and a pot in a warm room can dry in two days. Never let it wilt hard: an alocasia that collapses from thirst usually loses that leaf for good rather than recovering it.

It is also mite season if the plant is indoors in a dry room, and scorch season if you move it outside carelessly. Check leaf undersides every couple of weeks. If the plant goes outdoors, harden it off in shade over two weeks and shelter it from wind and prolonged rain.

Ease off feeding in a genuine heat wave. When the roots are already struggling at high temperatures, fertilizer damages them, and the result is dropped leaves within a week.

Autumn is about stopping things

The autumn work is almost entirely subtraction. Stop feeding before the room starts cooling, so nothing is left in the compost when growth stops. Start stretching the watering interval as soon as the plant stops replacing leaves. Bring any outdoor plant back in well before nights fall below 59F (15C), and wash it thoroughly first.

Do not repot, divide or cut back in autumn unless there is rot to deal with. A plant disturbed now goes into the cold half of the year with damaged roots and rarely comes through it.

1. Bring it in on the overnight low Judge by the forecast overnight minimum rather than how warm the afternoon feels. One cold night undoes a whole summer of growth.
2. Clean before it comes indoors Rinse the leaf undersides and scrub the outside and base of the pot. Pests carried into a warm dry room in autumn multiply far faster than they did outside.
3. Move it to the brightest spot you have As the light weakens, the summer position becomes too dark. Moving it back to the window is often the difference between holding its leaves and dropping the lot.

Winter and dormancy

Below about 59F (15C) an alocasia stops growing, and many plants retire their leaves one by one until nothing is left above the compost. This is normal and it is not death. The corm is intact underground and will send up new leaves when the room warms in spring, usually six to twelve weeks later.

The whole winter job is to keep the corm alive: warm enough, dry enough, and undisturbed. Water perhaps once every two to four weeks, enough to keep the compost barely damp rather than dust dry, and always on a mild morning so the surface dries before the cold of the night. Do not feed, do not repot, do not cut into the corm and do not throw the pot away because it looks empty.

If the pot looks empty, squeeze the corm through the compost before deciding anything. Hard means alive and dormant. Soft means rot. That one check saves most of the plants that get discarded every winter.

Records that make next year easier

An alocasia year is slow enough that memory is genuinely unreliable, and the useful information is all dates. Write down the date each new leaf unfurls, the date the last leaf fell in autumn, the date the first one appeared in spring, and the date you repotted and how many offsets and corms came out of the pot.

Add two figures about the room: the overnight low at the plant in the coldest week, and the week the heating went on. After one full cycle you can see exactly how long your dormancy lasts, whether your plant needs moving before winter, and how far ahead of the mite season you need to raise the humidity. It turns a plant that seems unpredictable into one that runs to a known pattern.

Note the position of each plant as well as its dates. When two plants of the same age behave completely differently, the answer is nearly always in where they were standing, and only a written note will tell you that a year later.