Ask Tomasgreen
How can I collect seeds from this mallow without picking too early?
Your pink mallow is still flowering freely, so the seeds are probably not ready. The deciding feature is not the flower, but the little capsules left after the petals fall.
Reader: @ullisgullis · · 2 min read

This is a mallow, and seed is collected only after the flower has faded. Your plant mainly shows open flowers and buds, so in late August it is often simply a matter of leaving some flowers in place rather than deadheading them.
How to tell when the seeds are ripe
Look behind where the flower was. After the petals fall, a rounded, slightly flattened seed capsule develops. Leave it to ripen on the plant until it is brown and dry rather than green and juicy. If unsure, wait a few extra days.
How to collect the seeds
- Cut or pinch off dry seed capsules in dry weather.
- Leave them indoors with good air circulation for a few days if they are not yet completely papery.
- Gently crumble the capsule apart and pick out the seeds.
- Let the seeds finish drying on paper before putting them in a paper bag or envelope.
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- Original reader contribution ↗Reader question