Geranium Fertilizer

Feed once weekly through the growing season, dosing by size: 1 Tbs (15mL) per gallon of water for plants under 6", 2 Tbs (30mL) per gallon for larger ones. A hose end sprayer set to those rates covers beds and window boxes fast. Container geraniums need the weekly rhythm most — frequent summer watering flushes nutrients out of pots quickly.

At 1 tsp per quart, the 8 oz bottle makes about 48 watering cans of feed. For a typical shelf of 10–15 plants fed every 1–2 weeks in season, that's several months of feeding — and the 32 oz bottle four times that.

Mostly a pruning issue, not a feeding one. Geraniums bloom on new growth, and unpinched plants stretch into bare-stemmed stalks with flowers only at the tips. Pinch growing tips through the season and cut leggy stems back hard — they respond well. Deadhead spent flower clusters down to the stem too. Excess nitrogen makes the stretching worse, which is why this formula keeps N at 3%.

Check watering first: geraniums hate sitting wet, and soggy soil yellows lower leaves fast — let pots dry between waterings and make sure drainage is clear. If watering is right, depleted potting mix is the likely cause, and yellowing between the veins on older leaves points specifically to magnesium. This formula supplies magnesium and iron alongside the bloom nutrition.

Both benefit, but they're different plants. What most people call geraniums — the classic red, pink, and white bedding and container plants — are pelargoniums, which this formula targets. True hardy geraniums (cranesbill) are perennials with a similar appetite, and the same bloom-weighted ratio suits them. Either way, follow the size-based label rates.

Lightly, if at all. Overwintered geraniums are being held rather than grown — most people cut them back and keep them cool and dry in reduced light, where feeding pushes weak growth the light can't support. The label's schedule runs through the growing season for that reason. Resume weekly feeding when you bring them back into light in late winter and new growth starts.

All the nitrogen is nitrate, absorbed directly by roots, so it starts working with the first watering. Expect deeper leaf color within 1-2 weeks, and yellowing lower leaves stabilizing as new growth comes in. Flower response follows in 3-4 weeks — more clusters and better color — since the plant has to initiate those buds first. Pair it with pinching for the fastest visible change.