Growli

Soil & potting mix

Best soil for Colocasia Fontanesii (Colocasia esculenta 'Fontanesii')

Also called violet-stemmed taro, black-stemmed taro.

More about colocasia fontanesii

About Colocasia Fontanesii

Colocasia esculenta 'Fontanesii' · also called violet-stemmed taro, black-stemmed taro · tropical

Colocasia esculenta 'Fontanesii' is the violet-stemmed taro, with large drooping green leaves on striking dark purple-black stems and veining. A vigorous, moisture-loving clumping aroid, it wants bright light, abundant water, warmth, and rich soil, and even thrives in boggy conditions. Bold and fast-growing, but toxic to pets and people like all Colocasia.

Preferred mix: Rich, moisture-retentive soil

Watch for — Brown, crispy leaf edges: Almost always underwatering or low humidity on this water-loving plant. Keep the soil constantly moist and humidity high.

Why colocasia fontanesii needs this mix

Colocasia Fontanesii hates drying out, so it wants a mix that stays evenly moist — but it still needs perlite so "moist" never tips into "waterlogged".

For the full picture on what makes up a good mix, see our guide to the main types of soil and potting media — it explains why each ingredient above behaves the way it does.

What goes wrong with the wrong mix

The wrong soil is one of the most common reasons colocasia fontanesii struggles, and the damage often shows up weeks later as a watering problem. For this species specifically:

Using a sharp, fast-draining "houseplant" or cactus-leaning mix that lets colocasia fontanesii dry out. It needs a moisture-retentive but still airy blend.

pH — does it matter for colocasia fontanesii?

Colocasia Fontanesii prefers a slightly acidic mix (around pH 5.5-6.5); a peat-free compost-and-coir blend sits there naturally, so routine pH testing is unnecessary.

If you want to check or adjust it, the soil pH guide walks through testing and the safe ways to nudge a mix more acidic or more alkaline.

DIY mix vs a bagged one

A good peat-free houseplant compost works for colocasia fontanesii straight from the bag if you mix in some perlite for air. The DIY ratio above gives a more reliable moisture-to-air balance.

Drainage and the pot

Use a pot with a drainage hole but a less-porous material (plastic or glazed) so it does not dry too fast. Bottom-watering keeps the mix evenly moist without sogging the crown.

Peat-free mixes slump and compact as they hold moisture, so refresh colocasia fontanesii's mix every 12-18 months to keep air in the rootball even if the pot size is unchanged. When the time comes, our repotting guide for colocasia fontanesii covers the timing and technique step by step.

Colocasia Fontanesii soil — frequently asked questions

What is the best soil mix for colocasia fontanesii?

3 parts peat-free houseplant compost : 1 part coco coir : 1 part perlite. Colocasia Fontanesii comes from damp, shaded forest floors and has fine roots that scorch and brown the moment the rootball dries — the mix has to hold a steady reserve.

Can I use normal potting soil for colocasia fontanesii?

A free-draining, gritty mix dries too fast for colocasia fontanesii — you get crispy brown edges and frond or leaf drop within days of one missed watering. A good peat-free houseplant compost works for colocasia fontanesii straight from the bag if you mix in some perlite for air. The DIY ratio above gives a more reliable moisture-to-air balance.

Does colocasia fontanesii need a special pH?

Colocasia Fontanesii prefers a slightly acidic mix (around pH 5.5-6.5); a peat-free compost-and-coir blend sits there naturally, so routine pH testing is unnecessary.

Should I buy a bagged mix or make my own for colocasia fontanesii?

A good peat-free houseplant compost works for colocasia fontanesii straight from the bag if you mix in some perlite for air. The DIY ratio above gives a more reliable moisture-to-air balance.

How often should I refresh the soil for colocasia fontanesii?

Peat-free mixes slump and compact as they hold moisture, so refresh colocasia fontanesii's mix every 12-18 months to keep air in the rootball even if the pot size is unchanged. Use a pot with a drainage hole but a less-porous material (plastic or glazed) so it does not dry too fast. Bottom-watering keeps the mix evenly moist without sogging the crown.

Keep reading