Hydroponics BC

Feeding and Watering in Hydroponics

Hydroponic Foods

For soil-less gardening in gravel, lava rock, rockwool and clay pellets


New rooted cuttings or very young plants from seed.

Feed: 1/2 strength Flower formula
1/3 teaspoon Calcium nitrate "B" (2 grams)
Dissolve in one gallon warm water, then add:
1/2 teaspoon flower food "C" (3.5 grams) and stir well. Feed every second time you water your garden


Plants in rapid growth with established root systems.

Use a food especially designed to promote vigorous green growth. (First time - feed at 1/2 strength)

1 teaspoon Calcium Nitrate "B" (6.5 grams)
Dissolve in one gallon warm water, then add 1 teaspoon Hydroponic Food "A" (8 grams) and stir well.

Feed as required and flush the root zone with lukewarm water regularly, especially when garden temperatures reach 90 degrees F. (32 degrees Celsius)


Plants that are producing flowers or fruit or that are large enough to begin crop production:
(1) Flush the root zone by gently running room temperature water through the roots. Large plants could require up to a gallon of water. This clears the soil of any leftover fertilizer from the "green growth" stage.

(2) Use "Flower Food" formula for flower and crop production. First time feed at half strength.

3/4 teaspoon Calcium Nitrate "B" (5 grams) (use only 1/2 teaspoon/gallon in hot growing conditions) 1-3/4 teaspoon Flower Food "C" (12 grams) and stir well. Feed as required. Remember to flush the roots with plan water regularly.


(a) These soil-less mixes hold a lot of food
(b) Feed every second time you water
(c) When you use plain water you re-dissolve the food held by the potting mix and make it available to the roots.


Always use room temperature water

Never fertilize a dry plant - water it well and feed an hour later

In hot weather conditions - feed only every third time you water (90 degrees F or higher) and reduce Nitrogen feed by a third in hydroponic systems

Let water stand overnight or stir it to drive off excess chlorine

For plants in soil or sunshine mix:
- feed every other time you water during normal growing conditions
- add dolomite lime (one Tablespoon per gallon of soil) as a top-dressing to soil and work it into soil after 2 months of growth

For plants in hydroponics:
- watch PH and food strength. It really helps!
- flush with straight water in hot weather

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