How to Overwinter Caladiums Indoors

The first time a frost warning hit my phone in early October, I figured my caladiums would “probably be fine for one night.” The next morning, every leaf looked like wet tissue paper—translucent, collapsed, and beyond saving. Here’s the surprise: caladiums don’t need a hard freeze to get wrecked. Cold, damp weather alone can start the rot clock ticking. The good news is overwintering caladiums indoors is straightforward once you treat them like what they are—tropical tubers that want warmth, dryness (at the right time), and patience.

This guide walks you through three reliable ways to overwinter caladiums indoors, plus how to troubleshoot the common failures (mold, shriveling, and mystery rot). I’ll give you specific temperatures, timing, and storage targets—because guessing is how tubers disappear.

Know what you’re overwintering: tubers, not “houseplants”

Caladiums (Caladium bicolor and hybrids) grow from tubers. Indoors, you can overwinter them in two main modes:

• Dormant tuber storage (most dependable): let foliage die back, dig, cure, and store the tubers dry.
• “Keep it growing” indoors (fussier): pot them up and maintain warmth and light through winter.

Most home gardeners get the best results with dormant storage because it avoids spider mites, weak winter growth, and the constant “is it too wet?” worry.

For timing and cold sensitivity, university sources are consistent: caladiums are injured by chilling and should be handled before cold weather settles in. The University of Florida IFAS Extension notes caladiums are tropical and should be lifted before cold temperatures (UF/IFAS Extension publication, 2020). North Carolina State Extension also emphasizes lifting tender bulbs/tubers prior to frost and storing them under cool (but not cold), dry conditions appropriate to the species (NC State Extension, 2023).

“Successful overwintering is mostly about preventing two things: chilling and moisture sitting on the tuber. Warm, dry storage after curing is what keeps caladiums alive until spring.” — paraphrased best-practice summary from extension storage recommendations (UF/IFAS Extension, 2020; NC State Extension, 2023)

Three real-world overwintering scenarios (pick yours)

Before the how-to, decide which situation matches your garden. Your method should fit your setup, not the other way around.

Scenario 1: Caladiums planted in the ground (short growing season)

If you garden where nights dip below 55°F (13°C) in early fall, dig them. Don’t wait for a hard frost—chilling damage can start earlier, especially in wet soil.

Scenario 2: Caladiums in outdoor containers (easy win)

Containers cool faster than the ground. Bring pots into a garage or basement to dry down, or dump and store the tubers. This is usually the simplest, cleanest overwintering route.

Scenario 3: You want caladiums as winter houseplants

It can be done, but you’ll need a bright window or grow light, warm indoor temps, and careful watering. Expect slower growth and smaller leaves unless you provide strong supplemental light.

Method comparison: dormant storage vs. keeping them growing

Step-by-step: overwinter caladiums as dormant tubers (most reliable)

This is the method I recommend if you want repeatable success year after year.

Timing: when to lift

• Plan to lift when night temperatures consistently fall below 55°F (13°C), or at least 1–2 weeks before your average first frost.
• If a frost is predicted within 48 hours, lift immediately—even if foliage still looks good.

Tools and supplies

• Garden fork or spade
• Pruners or scissors
• Cardboard box or crate with ventilation holes
• Dry packing medium: peat moss, coco coir, or vermiculite
• Paper bags or newspaper (optional)
• Marker and labels (caladium cultivars look identical as tubers)

1) Dig carefully (don’t spear the tuber)

1. Cut foliage back to about 2–3 inches tall if it’s already declining, or leave it on if still green (it helps you locate tubers).
2. Use a fork and start digging 6–8 inches away from the plant crown to avoid slicing the tuber.
3. Lift the clump and gently shake off loose soil.

2) Cure (this step prevents storage rot)

Curing toughens the skin and dries surface moisture so fungi don’t get a head start.

1. Place tubers in a single layer in a warm, airy spot out of sun (a garage shelf works well).
2. Target curing conditions: 70–80°F for 7–10 days.
3. Don’t wash tubers. If they’re muddy, let them dry, then brush soil off gently.

If you skip curing and pack tubers while they’re still cool and damp, you’re basically packing a tiny compost pile.

3) Clean up and sort

• After curing, trim off remaining stems close to the tuber.
• Inspect for soft spots, foul smell, or wet-looking patches.
• Discard tubers that are mushy or have spreading rot.

4) Pack for storage

1. Put 1–2 inches of dry packing medium in the bottom of a ventilated box.
2. Set tubers so they aren’t touching (a little space reduces spread if one goes bad).
3. Cover with another 1–2 inches of medium.
4. Label the box with cultivar and date.

5) Store at the right temperature

Store packed tubers at 60–70°F. That “room temperature closet” is often better than a cold basement. Avoid areas that dip below 50°F; chilling injury can show up later as poor sprouting or rot.

Extension guidance for tender bulbs/tubers commonly emphasizes dry storage and avoiding freezing temperatures, with species-specific temperature targets (NC State Extension, 2023). Caladium-specific recommendations also stress warmth during storage (UF/IFAS Extension, 2020).

Monthly check (5 minutes that saves your stash)

• Once every 3–4 weeks, open the box.
• Remove any tubers showing mold or soft spots.
• If tubers are shriveling badly, lightly mist the packing medium once (do not wet the tubers).

Option: overwinter caladiums in pots (semi-dormant storage)

If you have several large containers and don’t want the mess of digging and cleaning, this compromise can work.

How to do it

1. Before frost, move pots indoors to a warm, dry location (aim for 60–70°F).
2. Stop fertilizing by late summer; let the plant naturally slow down.
3. As leaves yellow, reduce watering until you’re barely moistening the mix.
4. After foliage dies back, cut stems to 1–2 inches.
5. Store the pot in a dim spot. Water only if the mix becomes bone dry—about 1–2 tablespoons every 4–6 weeks is usually plenty, depending on pot size and indoor humidity.

When this fails

• Rot happens because the center of the pot stays damp longer than you think.
• Fungus gnats show up if the potting mix never truly dries.

If you’ve lost caladiums this way before, switch to digging and boxed storage. It’s more work upfront, but much more predictable.

Option: keep caladiums growing indoors (houseplant mode)

This is the route for gardeners who enjoy fussing a little and have decent light. The goal is to prevent dormancy by providing warmth, light, and steady—but not soggy—moisture.

Light (what “bright” really means)

• Place near an east or bright north window, or a few feet back from a sunny south/west window with sheer curtain.
• Under grow lights, aim for 12–14 hours/day.
• If leaves get smaller and stems stretch, it’s not “winter normal”—it’s low light.

Watering (indoors is where people drown them)

Indoors, caladiums use less water. Water only when the top 1 inch of mix is dry. Then water thoroughly until it drains, and empty the saucer. If your potting mix stays wet for more than 5–7 days, you need more light, a warmer room, or a chunkier mix.

Soil (potting mix that prevents winter rot)

Use a well-drained mix. A practical blend:

• 2 parts quality potting mix
• 1 part perlite or fine orchid bark

Avoid heavy mixes that feel “muddy” when wet. Winter root rot is usually a soil-structure problem first, and a watering problem second.

Temperature and humidity

• Keep between 65–80°F.
• Avoid cold windowsills; 55°F nights can trigger decline.
• Average indoor humidity is usually acceptable, but keep plants away from heating vents.

Feeding (less than you think)

• If you’re maintaining active growth: feed at 1/4 strength with a balanced liquid fertilizer every 4–6 weeks.
• If growth slows: stop feeding entirely until spring.

Overfeeding in low light gives you soft, weak growth that attracts pests.

Common problems (and what actually fixes them)

Overwintering problems are usually predictable. Match the symptom to the cause instead of reacting with random extra water or fertilizer.

Troubleshooting: tubers get moldy in storage

Symptoms: white/gray fuzzy growth on tubers or packing medium; musty smell.

Likely causes: tubers packed before curing; storage too humid; tubers touching; medium damp.

Fix:

• Remove affected tubers and inspect—if firm, wipe mold off with a dry paper towel and let air-dry 24 hours before repacking.
• Replace packing medium if it feels damp.
• Improve airflow: add vent holes or switch to a slatted crate.
• Store warmer and drier (target 60–70°F).

Troubleshooting: tubers shrivel or feel hollow

Symptoms: tubers are lightweight, wrinkled, or “deflated.”

Likely causes: storage too dry; tubers were small/young; curing area too hot/long.

Fix:

• Lightly mist packing medium once, then close the box (do not spray tubers directly).
• Move storage away from heat sources; avoid shelves above furnaces/water heaters.
• Next season, give caladiums a longer growing season and steady summer moisture so tubers size up.

Troubleshooting: tubers rot from the inside out

Symptoms: tuber looks fine outside but is soft when squeezed; brown interior.

Likely causes: chilling injury before digging; stored too cold (below 50–55°F); packed with damaged tubers.

Fix:

• Store warmer (again: 60–70°F is your friend).
• Dig earlier next fall—before extended cool, wet weather.
• Handle gently; any cuts invite rot.

Troubleshooting: indoor plants get yellow leaves and stop growing

Symptoms: yellowing, leaf drop, limp stems.

Likely causes: natural dormancy triggered by low light or cool temps; overwatering in winter.

Fix:

• If you want dormancy: stop watering once most leaves yellow and follow the tuber storage method.
• If you want to keep growing: increase light (grow light 12–14 hours), keep temps above 65°F, and let the top 1 inch dry between waterings.

Troubleshooting: spider mites on overwintered caladiums

Symptoms: stippled leaves, fine webbing, dusty-looking foliage—especially in dry, heated rooms.

Fix:

• Rinse leaves thoroughly in the sink or shower.
• Repeat every 5–7 days for 3 rounds to break the life cycle.
• Improve humidity slightly and keep plants away from heating vents.

Watering, soil, light, and feeding—winter rules that prevent losses

Watering (the winter reset)

Overwintering success is mostly moisture management. Pick the rule set that matches your method:

• Dormant tubers in a box: no watering. You’re managing dryness, not “keeping them alive with water.”
• Pots stored semi-dormant: almost no watering. If the mix is dusty-dry all the way down, add a tiny amount.
• Actively growing indoors: water only when the top 1 inch is dry; never let the pot sit in water.

Soil (drainage beats “rich” in winter)

For indoor growth, soil structure is your insurance policy. A mix that drains in under a minute and doesn’t stay soggy for a week will prevent most winter rot episodes.

Light (don’t pretend a dim room is “bright indirect”)

Caladiums can tolerate shade outdoors, but winter indoor light is a different animal. If you don’t have a genuinely bright window, a grow light is the difference between a plant that limps along and one that actually holds its color.

Feeding (timing matters more than brand)

Feeding dormant tubers is pointless—they’re not taking anything up. For active plants, light feeding is fine, but don’t fertilize a plant that’s slowing down. You’ll just create soft growth and invite pests.

Spring wake-up plan (so overwintering actually pays off)

Overwintering isn’t finished until you get strong sprouting again.

When to start them

• Start tubers indoors 6–8 weeks before your last expected frost if you want a head start.
• Or pot them up when indoor temps are reliably 70°F and you can keep the soil warm.

How to pot up stored tubers

1. Choose a pot with drainage holes. For one large tuber, a 6–8 inch pot is usually plenty.
2. Plant about 1–2 inches deep, with the knobby side (buds) up.
3. Water once to settle soil, then keep barely moist until you see growth.
4. After sprouting, water more regularly—still avoiding soggy soil.

If sprouting is slow, bottom heat helps. A warm spot (top of a fridge, near a heat register but not in the airflow) can make a noticeable difference, because caladiums respond strongly to warm soil.

A few hard-won habits that make overwintering boring (in a good way)

If you want this to become routine instead of a yearly gamble, focus on these practices:

• Dig earlier than you think. Cool, wet fall soil is more dangerous than you expect.
• Cure every time. Give tubers that 7–10 day warm, airy dry-down.
• Store warm, not cold. Aim for 60–70°F, not basement-chilly.
• Check monthly. One rotting tuber can take others with it if they’re touching.
• Label cultivars. Tubers all look the same in January.

Once you’ve overwintered caladiums successfully, you stop buying new ones every spring—and you also get bigger, better displays because mature tubers perform. Treat them like the tropical tubers they are, keep them warm and dry through winter, and they’ll repay you with a faster start when real heat returns.

Sources: University of Florida IFAS Extension caladium guidance (2020); North Carolina State Extension guidance on storing tender bulbs/tubers (2023).