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Soil & potting mix

Best soil for Cistus-Flowered Sundew (Drosera cistiflora)

Also called cistus-flowered sundew.

More about cistus-flowered sundew

About Cistus-Flowered Sundew

Drosera cistiflora · also called cistus-flowered sundew · houseplant

Drosera cistiflora is a spectacular tuberous sundew from South Africa's Western Cape, prized for its unusually large, showy flowers — typically deep red, pink, or white — that rival a rockrose in size. It follows a Mediterranean-type seasonal cycle: active in the cool, wet winter and dormant as a tuber through the hot, dry summer.

Preferred mix: Very well-drained, low-nutrient sandy mix

Watch for — Fungal stem rot at soil level: Poor drainage or over-humid, stagnant air around the stem causes Botrytis or Pythium. Use the sandy, free-draining mix described, ensure good ventilation, and water from below only.

Why cistus-flowered sundew needs this mix

Cistus-Flowered Sundew is a true acid-lover — it physically cannot take up iron above about pH 5.5, so an ericaceous mix is not optional, it is survival.

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 cistus-flowered sundew struggles, and the damage often shows up weeks later as a watering problem. For this species specifically:

Planting cistus-flowered sundew in standard compost or limey garden soil. Without an acidic (ericaceous) medium it will yellow and fail no matter how well you water and feed it.

pH — does it matter for cistus-flowered sundew?

This is the whole game: Cistus-Flowered Sundew needs pH 4.5-5.5. Test it, use ericaceous compost (and an ericaceous feed), and water with rainwater where you can to keep the pH from creeping up.

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

Bagged ericaceous compost is the correct, easy base for cistus-flowered sundew; just open it up with bark and grit per the ratio above. Do not try to acidify ordinary compost by guesswork — it rarely holds.

Drainage and the pot

Containers are often easier than open ground because you control the pH completely. Use a pot with good drainage and an ericaceous mix; never let it sit waterlogged.

Top up or refresh the ericaceous mix yearly and test the pH each spring — it naturally drifts upward over time, especially if watered with tap water. When the time comes, our repotting guide for cistus-flowered sundew covers the timing and technique step by step.

Cistus-Flowered Sundew soil — frequently asked questions

What is the best soil mix for cistus-flowered sundew?

3 parts ericaceous (acidic) compost : 1 part composted pine bark or pine needles : 1 part perlite or coarse grit. Cistus-Flowered Sundew has evolved on acidic, peaty ground and depends on soil fungi that only function in acid conditions — raise the pH and it starves even in "rich" soil.

Can I use normal potting soil for cistus-flowered sundew?

Ordinary multipurpose or garden compost is far too alkaline for cistus-flowered sundew — expect classic yellowing, weak growth and a slow decline over a season or two. Bagged ericaceous compost is the correct, easy base for cistus-flowered sundew; just open it up with bark and grit per the ratio above. Do not try to acidify ordinary compost by guesswork — it rarely holds.

Does cistus-flowered sundew need a special pH?

This is the whole game: Cistus-Flowered Sundew needs pH 4.5-5.5. Test it, use ericaceous compost (and an ericaceous feed), and water with rainwater where you can to keep the pH from creeping up.

Should I buy a bagged mix or make my own for cistus-flowered sundew?

Bagged ericaceous compost is the correct, easy base for cistus-flowered sundew; just open it up with bark and grit per the ratio above. Do not try to acidify ordinary compost by guesswork — it rarely holds.

How often should I refresh the soil for cistus-flowered sundew?

Top up or refresh the ericaceous mix yearly and test the pH each spring — it naturally drifts upward over time, especially if watered with tap water. Containers are often easier than open ground because you control the pH completely. Use a pot with good drainage and an ericaceous mix; never let it sit waterlogged.

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