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Getting it to bloom

Why won't my Common Mallow bloom? (and how to make it flower)

Also called Common Mallow, High Mallow, Tall Mallow, Cheese Mallow (Malva sylvestris).

More about common mallow

About Common Mallow

Malva sylvestris · also called Common Mallow, High Mallow · flowering

Malva sylvestris is a robust biennial or short-lived perennial wildflower native throughout Europe, North Africa, and western Asia, widely naturalised worldwide. It colonises roadsides, waste ground, and hedgebanks, preferring full sun and well-drained soils; once established its deep taproot gives exceptional drought tolerance — but it dislikes being transplanted. The showy purple-veined mauve flowers appear from June to October. Common mallow is not toxic to cats, dogs, or humans and the young leaves and unripe seed pods are traditionally eaten as food.

Plant type: flowering

The reasons common mallow isn't blooming

Almost every non-blooming common mallow traces back to one of these, roughly in order of how common they are:

  1. Too little sun — most of these need full sun (or very bright light) to flower well; shade gives leaves, not blooms.
  2. Too much nitrogen feed, driving lush foliage at the expense of flowers (very common with general or lawn feeds).
  3. The plant has not been deadheaded, so it stops flowering once it sets seed.
  4. Irregular watering — drought or waterlogging at the budding stage makes buds abort.
  5. It is still too young or was checked by a transplant and is rebuilding before flowering.

Feeding common mallow a high-nitrogen general feed and growing it in too little sun — you get a big leafy plant and almost no flowers.

The fix — how to get common mallow to flower

  1. Maximise sun. Give common mallow the sunniest spot you have — for most bedding and fruiting plants, more direct light directly means more flowers.
  2. Switch the feed. Move off high-nitrogen feeds and use a higher-potassium "bloom" or tomato-type feed as it comes into flower.
  3. Deadhead regularly. Remove spent flowers often to keep it producing more rather than stopping to set seed.
  4. Water consistently. Keep moisture even through budding and flowering — drought-then-flood swings make buds drop.

Light and feeding do most of the heavy lifting here. Dial in the spot with the light guide for common mallow and get the feeding right with the common mallow fertilising schedule — the wrong feed (too much nitrogen) is one of the most common silent reasons a healthy plant makes leaves instead of flowers.

Bloom season and what to expect

Common Mallow flowers across its growing season (mostly summer) and, kept fed and deadheaded, can bloom for many weeks or right up to frost.

Post-bloom care so it flowers again

Deadhead, keep feeding lightly, and many will rebloom; collect seed from the best plants at the end of the season if you want to grow them again.

For everything else this plant needs day to day, see the full common mallow care brief and its watering schedule — a stressed, badly watered plant rarely has the energy to flower at all.

Common Mallow blooming — frequently asked questions

Why won't my common mallow flower?

Common Mallow blooms on the season's growth given enough sun, warmth and the right feed — there is no cold or photoperiod trick, just good growing conditions and a bloom-leaning feed. The most common reason it is not happening: Too little sun — most of these need full sun (or very bright light) to flower well; shade gives leaves, not blooms.

How do I make common mallow bloom?

Give common mallow the sunniest spot you have — for most bedding and fruiting plants, more direct light directly means more flowers. Move off high-nitrogen feeds and use a higher-potassium "bloom" or tomato-type feed as it comes into flower.

When does common mallow normally bloom?

Common Mallow flowers across its growing season (mostly summer) and, kept fed and deadheaded, can bloom for many weeks or right up to frost.

What should I do with common mallow after it flowers?

Deadhead, keep feeding lightly, and many will rebloom; collect seed from the best plants at the end of the season if you want to grow them again.

What is the single biggest mistake stopping common mallow flowering?

Feeding common mallow a high-nitrogen general feed and growing it in too little sun — you get a big leafy plant and almost no flowers.

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