Water Garden Fertilizer for Pond Plants

When your water garden may benefit from feeding

During spring and summer, when water lilies, lotus and marginals are actively growing
When lily pads come in pale or yellowing, the first sign aquatic plants show when iron runs short
For potassium, the nutrient water lilies and marginals run short of in a closed pond
When flowering water plants set few buds even with six hours of sun and room in the basket
In container water features and small ponds, dosed to their actual volume

Bloom and growth in a pond also depend on sunlight, water temperature, planting space and dosing to the pond's actual volume, so feeding is one part of water-garden care.

Results you can see

Feeds foliage for deeper color and a brighter, more lively look.

Encourages fresh leaf and stem growth for a fuller, thriving plant.

Supports healthy, resilient roots that absorb nutrients more effectively.

Works for water garden plants

Water Lilies
Lotus
Water Iris
Pickerel Rush
Cattails
Water Hyacinth
Marsh Marigold
Taro

How to use

Pond or water feature

1 tsp per 10 gallons of water, ideally added in a high flow area

Once a week in high light or summer
Pond or water feature (low light / winter)

1 tsp per 10 gallons of water, ideally added in a high flow area

Once monthly
Alternative measurement — large ponds

1 oz per 60 gallons of water

Same schedule
Alternative measurement — by volume

3/4 tsp per cubic foot of water

Same schedule

What's inside

A 1-0.5-3 ratio, and every number is set with pond chemistry in mind. Nitrogen holds at just 1% — all nitrate nitrogen, absorbed directly by plants — and phosphate at 0.5%, because in a pond, excess nitrogen and phosphorus don't stay unused: they feed the algae that turns water green and starves submerged plants of light. Potassium leads at 3%, the nutrient water lilies and marginals actually run short of in a closed system, supporting leaf production, stem strength, and flower color.

Beyond NPK: sea kelp (Ascophyllum nodosum) for natural growth compounds, plus 0.5% calcium and 0.25% magnesium, with iron, sulfur, manganese, zinc, copper, boron, and molybdenum. Iron is the one aquatic plants run short of first — it drives chlorophyll production, and in pond water it precipitates out of solution quickly, showing as pale, yellowing lily pads and weak growth even in a pond that looks otherwise healthy.

Label facts

NPK 1-0.5-3 with 0.5% calcium, 0.25% magnesium and 0.05% sulfur, plus iron, manganese, zinc, boron, copper and molybdenum.

Derived from kelp (ascophyllum nodosum), potassium phosphate, potassium nitrate, calcium nitrate, magnesium nitrate, boric acid, copper sulfate, ferric sulfate, manganese sulfate, zinc sulfate.

Store cool and dark. Guaranteed 12 months from purchase; keeps up to 2 years.

Frequently asked questions

How much fertilizer does my pond need?

Water Garden Fertilizer is dosed by water volume, not by plant, so start by working out how many gallons your pond holds. Add 1 teaspoon per 10 gallons, or 1 ounce per 60 gallons for larger ponds, or ¾ teaspoon per cubic foot of water. Pour it in near a pump, waterfall or other high-flow spot so it distributes evenly. Apply once a week in summer and high light, dropping to once a month in low light and winter when plant growth slows.

Can I use this in a pond with koi and goldfish?

Water Garden Fertilizer is formulated for planted ponds, including ponds with koi and goldfish, and its low nitrogen and phosphate levels reflect that fish are usually part of the system. Dose for your actual water volume, 1 teaspoon per 10 gallons, rather than estimating high; overdosing any fertilizer in a closed body of water stresses fish. If you keep valuable koi, add the first dose at the low end and watch for a day before settling into the weekly summer schedule.

Won't fertilizing my pond cause algae?

Water Garden Fertilizer is formulated to help minimize algae growth by keeping nitrogen and phosphate low, 1% nitrogen and 0.5% phosphate, while potassium at 3% carries the nutrition; potassium is the nutrient water lilies and marginals run short of in a closed system. Dosing for your actual volume still matters: the same product overapplied in a small pond can tip the balance toward green water.

Why aren't my water lilies blooming?

Usually light or crowding rather than feeding. Water lilies need at least six hours of direct sun to flower well, and a shaded pond won’t produce many blooms whatever you add to it. Crowded rootstock in an undersized planting basket is the other common cause; lilies need dividing every couple of years. Water Garden Fertilizer supports flowering once light and space are right, with potassium for stem strength and flower color, but it can’t substitute for either one.

Can I use regular plant fertilizer in a pond?

It’s a poor fit. Garden and houseplant formulas run high in nitrogen and phosphate, which in a pond feeds algae rather than plants and can foul the water for fish. Water Garden Fertilizer is built for the whole-water approach, with 1% nitrogen, 0.5% phosphate and potassium leading, so it feeds lilies and marginals through the water without tipping the pond toward green. Aquatic tabs pressed into planting baskets work differently, feeding at the root without dispersing. Match the product to the system.

When will I see results?

Greener pads and new growth show the difference first in warm, bright conditions, with flowering following as plants build the resources to bud. The nitrate nitrogen and dissolved minerals in Water Garden Fertilizer are available to aquatic plants as soon as they’re in the water, with no soil to move through. Iron in the formula addresses the pale, yellowing pads aquatic plants show first. Cool water slows everything, which is why winter dosing drops to monthly.

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