Growli

Soil & potting mix

Best soil for Zantedeschia 'Picasso' (Zantedeschia 'Picasso')

Also called Picasso calla lily, purple-edged calla.

More about zantedeschia 'picasso'

About Zantedeschia 'Picasso'

Zantedeschia 'Picasso' · also called Picasso calla lily, purple-edged calla · flowering

Zantedeschia 'Picasso' is a striking hybrid calla lily with two-tone spathes: creamy white flushed with deep violet-purple toward the throat and edges. Its dark green leaves are often silver-spotted. Grown from rhizomes, it flowers in summer in pots and borders, wanting bright indirect light, moist free-draining soil, and a dry winter rest at about 40-50 cm.

Preferred mix: Rich, moisture-retentive yet free-draining potting mix

Watch for — Rhizome rot: The most common killer; cold, wet compost rots the rhizome. Use free-draining mix, water moderately, and keep dry in dormancy.

Why zantedeschia 'picasso' needs this mix

Zantedeschia 'Picasso' 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 zantedeschia 'picasso' 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 zantedeschia 'picasso' dry out. It needs a moisture-retentive but still airy blend.

pH — does it matter for zantedeschia 'picasso'?

Zantedeschia 'Picasso' 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 zantedeschia 'picasso' 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 zantedeschia 'picasso''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 zantedeschia 'picasso' covers the timing and technique step by step.

Zantedeschia 'Picasso' soil — frequently asked questions

What is the best soil mix for zantedeschia 'picasso'?

3 parts peat-free houseplant compost : 1 part coco coir : 1 part perlite. Zantedeschia 'Picasso' 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 zantedeschia 'picasso'?

A free-draining, gritty mix dries too fast for zantedeschia 'picasso' — you get crispy brown edges and frond or leaf drop within days of one missed watering. A good peat-free houseplant compost works for zantedeschia 'picasso' 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 zantedeschia 'picasso' need a special pH?

Zantedeschia 'Picasso' 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 zantedeschia 'picasso'?

A good peat-free houseplant compost works for zantedeschia 'picasso' 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 zantedeschia 'picasso'?

Peat-free mixes slump and compact as they hold moisture, so refresh zantedeschia 'picasso''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.

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