Lesson 2
Feeding — when, how much, and what with
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Compost has 4–8 weeks of feed in it when you buy it. After that, plants in pots are entirely dependent on you for food. The two macro-rhythms: a slow-release granule at potting time, and a weekly liquid feed in the growing season.
A reliable feeding rhythm
- 1Spring potting: mix slow-release organic granules into fresh compost.
- 2Once leaves are growing fast: weekly liquid seaweed at half strength.
- 3When flower buds appear: switch to a high-potash (tomato) feed once a week.
- 4Stop feeding 2 weeks before the first hard frost — let plants harden off.
- 5Winter: no feed. Less water. Cooler, brighter spot if possible.
Reading the leaves
- Yellowing lower leaves, pale overall — nitrogen low. Feed weekly with a balanced feed.
- Purple leaf undersides on tomatoes/peppers — phosphate low or cold roots. Warm + tomato feed.
- Brown leaf edges, weak stems — potassium low. Switch to a tomato or comfrey feed.
- Lush green leaves but no flowers — too much nitrogen. Switch to high-potash (tomato) feed.