Short answer: for most container plants, mix ¼ to ½ teaspoon per gallon of water for regular maintenance feeding, and up to 2 teaspoons per gallon every 2 to 4 weeks for heavy feeders like citrus and fruit trees. Here's the full breakdown by crop and growth stage, along with the actual nitrogen concentration each rate delivers.
General feeding rates
| Feeding Stage | Dose | Frequency |
|---|---|---|
| Maintenance | ¼–½ tsp. (1.25–2.5 mL) per gallon of water | Every watering |
| Production | 1 tsp. (5 mL) per gallon of water | Weekly |
| Heavy Feeders | 2 tsp. (10 mL) per gallon of water | Every 2–4 weeks |
| Transplants | ¼ tsp. (1.25 mL) per gallon of water | First 2 weeks, then switch to Maintenance |
Reduce feeding frequency during periods of slow growth or dormancy, typically late fall through winter for most container plants.
What these rates actually deliver
Teaspoon measurements only tell part of the story, since fertilizer concentration depends on the product's density and nitrogen percentage, not just the volume you measure out. Here's what each rate delivers in actual nitrogen concentration (parts per million, or ppm):
| Dose | Nitrogen Delivered |
|---|---|
| ¼ tsp./gal | ~36 ppm N |
| ½ tsp./gal | ~72 ppm N |
| 1 tsp./gal | ~143 ppm N |
| 2 tsp./gal | ~286 ppm N |
This matters because ppm N, not teaspoons, is the actual agronomic target. If you're used to a different liquid fertilizer brand and trying to translate dosing between products, match the ppm N rather than the volume measurement, since different products vary in both density and nutrient concentration.
Feeding by crop
Houseplants, vegetables, and general garden plants
For most plants growing in containers, raised beds, or in-ground, the standard rates above apply directly:
- Active growth (spring/summer): ¼–½ tsp. per gallon with every watering, or 1 tsp. per gallon weekly
- Slower growth (fall/winter): drop to a lighter feeding schedule or skip for a few weeks at a time
This covers houseplants, vegetable gardens, roses and flowering perennials, and general landscape and container plants. The crop-specific notes below are for plants with feeding needs that differ meaningfully from this baseline.
Citrus (lemon, lime, orange, grapefruit, kumquat)
Citrus are heavy nitrogen feeders, especially during active growth in spring and summer.
- Spring through summer (active growth): 1 tsp. per gallon, weekly
- Heavy feeding boost during fruit development: 2 tsp. per gallon, every 2–4 weeks
- Fall and winter (dormancy): reduce to Maintenance rate, ¼–½ tsp. per gallon, or skip feeding entirely if the tree is fully dormant
Citrus is chloride-sensitive, so a chloride-free formula matters here more than for most other crops.
Fruit trees (fig, banana, and similar heavy feeders)
Treat similarly to citrus: weekly Production-rate feeding through the active growing season, stepping up to the Heavy Feeder rate during fruit set and development, then tapering off as growth slows heading into dormancy.
Newly transplanted plants
Use the reduced Transplant rate (¼ tsp. per gallon) for the first two weeks after transplanting or repotting, regardless of crop. New or disturbed root systems are more sensitive to fertilizer salts, even at rates that would be perfectly fine for an established plant. After two weeks, move to the standard Maintenance rate for that crop.
A note on overfeeding
More fertilizer isn't better. Exceeding the Heavy Feeder rate, or feeding at full strength every single watering instead of rotating in plain water, increases the risk of salt buildup in the soil regardless of which fertilizer you're using. If you see leaf-tip browning or a white crust forming on the soil surface or pot rim, that's usually a sign to flush the container with plain water and scale back your feeding frequency.
Frequently Asked Questions
How often should I fertilize citrus trees? Weekly during active spring and summer growth, scaling up to every 2–4 weeks at a stronger dose during fruit development, then tapering to monthly or stopping entirely during winter dormancy.
Can I overfeed my houseplants with 9-3-6 fertilizer? Yes. Feeding at full strength every watering without ever using plain water increases the risk of salt buildup in the potting mix. Rotating in plain water between feedings, or using the lighter Maintenance rate, reduces this risk.
Do I need to adjust dosing for a newly repotted plant? Yes. Use a reduced rate (about ¼ teaspoon per gallon) for the first two weeks after transplanting, since disturbed root systems are more sensitive to fertilizer salts than established ones.