Fertilizer Dilution Calculator
Dilute liquid fertilizer to full, half, or quarter strength without guessing.
Always dissolve fertilizer fully and only feed when the soil is already damp, never onto bone-dry roots.
Stop guessing your fertilizer dose
Fertilizer labels are written for the bottle, not for your watering can, and "dilute to half strength" is a recipe for guesswork. Enter the label dose, choose how strong you want to feed, and tell the calculator how big your watering can is. It does the rest.
How often should I feed?
During spring and summer, feeding at half strength every 2-4 weeks suits most houseplants. Cut back or stop entirely in autumn and winter when growth slows.
Frequently Asked Questions
What does "half strength" actually mean?
It means using half the fertilizer the label recommends for the same amount of water. Most houseplant growers feed at half or quarter strength during the growing season because it’s gentler on roots and lowers the risk of fertilizer burn.
Is it better to under-fertilize or over-fertilize?
Under-fertilize. Too little simply slows growth, which is easy to fix. Too much causes salt build-up, brown leaf tips, and root damage. When in doubt, dilute more and feed less often.
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