Potassium Sulfate Fertilizer
Potassium sulfate for plants that adds potassium plus sulfur with no chloride. Clean potassium feeding for fruit, blooms, and sensitive crops.
Use it as a targeted supplement alongside your normal feeding program, following the label rate so you can add the specific nutrition your plants need without complicating the routine.
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Potassium Sulfate Fertilizer with a 0-0-10 analysis plus sulfur — a potassium feed that also supplies sulfur, with no nitrogen or phosphorus, made to strengthen plants for flowering, fruiting, and stress tolerance. Sulfate of potash is the potassium source many growers prefer for salt-sensitive and edible crops, and here it pairs 10% soluble potash with 2% sulfur for fruit quality and overall vigor.
How to Use Potassium Sulfate Fertilizer
| Method | Amount | How Often |
|---|---|---|
| Watering can | 2 Tbs (30mL) per gallon of water | Spring & Summer: every 1-2 weeks |
| Watering can | Same dilution | Fall & Winter: every 4 weeks |
| Hose-end sprayer | Set dial to 1 oz (30mL) setting | Spring & Summer: every 1-2 weeks |
| Leaf misting (optional) | 1 tsp per quart (32 oz) of water, spray on leaves | every 1-2 weeks |
Use as a potassium supplement alongside your regular feeding, not in place of it — with no nitrogen or phosphorus, this targets potassium and sulfur specifically.
What's Inside
The 0-0-10 analysis supplies potassium with no nitrogen or phosphorus, plus 2% sulfur — a combination that comes from sulfate of potash. Potassium is the nutrient that regulates water movement, builds fruit quality and sweetness, strengthens stems, and drives tolerance of heat, drought, and cold, while the sulfur is a secondary nutrient that supports proteins and chlorophyll. Delivering both together is the hallmark of a potassium sulfate feed, and it's why this is often chosen for the flowering and fruiting stage.
Beyond NPK: this is a focused potassium-and-sulfur feed, not a full-spectrum blend, so it doesn't carry a nitrogen, phosphorus, or micronutrient package. Sulfate of potash is valued because it delivers potassium with less chloride than muriate of potash, which suits salt-sensitive and edible crops that can be set back by chloride buildup. Use it to correct a potassium shortfall or support fruiting in season, alongside a complete fertilizer that covers the plant's other needs.
Made For
Built as a potassium-and-sulfur supplement for fruiting and flowering plants, and especially for salt-sensitive and edible crops — tomatoes, peppers, potatoes, berries, and fruit — where sulfate of potash is preferred over chloride-based potassium, used alongside a complete fertilizer.
Problems It Solves
- Poor or low-quality fruit needing more potassium
- Scorching along the edges of older leaves
- Salt-sensitive crops needing a low-chloride potassium source
- Weak stems and poor heat or drought tolerance
FAQs
How often should I use potassium sulfate fertilizer?
During spring and summer, apply every 1-2 weeks with 2 Tbsp per gallon in a watering can, or use the hose-end sprayer on the 1 oz setting. In fall and winter, cut back to once every 4 weeks. Because it supplies potassium and sulfur but no nitrogen or phosphorus, use it as a supplement alongside your regular complete feed, mainly during the flowering and fruiting stage or to correct a potassium shortfall.
What's the difference between potassium sulfate and muriate of potash?
Both supply potassium, but potassium sulfate (sulfate of potash) delivers it with sulfur and much less chloride, while muriate of potash (potassium chloride) is chloride-based. The lower chloride matters for salt-sensitive crops — many vegetables, berries, potatoes, and tobacco — which can be set back by chloride buildup in the soil. Sulfate of potash is the premium choice for those crops and for edible gardens, while muriate is common in general agriculture where chloride sensitivity isn't a concern.
What are the signs my plant needs potassium?
The classic sign is scorching or yellowing along the edges and tips of older, lower leaves while the leaf centers stay green — potassium moves to new growth first, so deficiency shows on old leaves. Weak stems, poor fruit quality, and low stress tolerance are others. If instead you see uniform whole-leaf yellowing, that's nitrogen, and interveinal yellowing points to magnesium or iron, so match the pattern before treating.
Is this good for vegetables and fruit?
Yes — it's an especially good fit for edible crops. Sulfate of potash delivers the potassium that drives fruit size, sweetness, and quality without the chloride that muriate-based potassium adds, which is why it's favored for vegetables, potatoes, berries, and fruit. The added sulfur is a bonus for crops like onions and garlic that use sulfur heavily. Feed during the fruiting stage alongside a complete fertilizer for the best fruit quality.
When will I see results?
Potassium deficiency symptoms on existing leaves won't reverse, but new growth comes in stronger, and fruit developing after feeding shows better quality over the following weeks. Stem strength and stress tolerance improve gradually as the plant takes up potassium. The clearest results come across a full fruiting cycle of consistent feeding rather than immediately.
Related Products
Sulfate Of Potash Potassium Fertilizer Potassium Nitrate Fertilizer