Description
Stark® Soil Acidifier solves a problem that fertilizing alone can’t fix: when soil pH is too high, acid-loving plants can’t absorb the nutrients already in the soil, no matter how much you feed them. Blueberries, cranberries, lingonberries, and blue hydrangeas all require acidic soil conditions to thrive — and in much of the country, native soil is simply too alkaline to support them without amendment. Stark® Soil Acidifier’s sulfur-based formula lowers soil pH to create the conditions these plants need to actually use what’s available in the soil. Apply prior to planting for best results, or work into the root zone of existing plants.
Why pH Matters More Than Fertilizer for Acid-Loving Plants
Blueberries require a soil pH of 4.2-5.0. At a pH of 6.5 — which is perfectly suitable for most vegetables and fruit trees — blueberries can’t access iron, manganese, and other micronutrients even when those nutrients are physically present in the soil. The plant looks deficient, growth slows, and fruit production suffers, even in heavily fertilized conditions. Lowering pH with a sulfur-based acidifier unlocks those nutrients and restores the plant’s ability to grow and produce as it should.
Blue Hydrangeas — pH Controls Bloom Color
Soil pH doesn’t just affect plant health for hydrangeas — it controls bloom color. Bigleaf hydrangeas bloom blue in acidic soil and pink in alkaline soil. For gardeners who want blue hydrangea blooms and are working with neutral or alkaline soil, Stark® Soil Acidifier is the practical tool for shifting pH in the right direction and keeping it there through the growing season.
How to Apply
For best results, apply prior to planting and incorporate into the soil. One cup of Stark® Soil Acidifier covers one square yard of the planted area.
For existing plants, sprinkle evenly over the root zone and work into the top inch of soil. Water thoroughly after application. Check soil pH regularly and reapply as needed to maintain the target range.
Always read and follow the label:
Front - Download The Label
Back - Download The Label
Why Growers Choose Stark® Soil Acidifier
- Lowers soil pH for acid-loving plants — blueberries, cranberries, lingonberries, and hydrangeas
- Sulfur-based formula — the proven mechanism for sustained pH reduction
- Unlocks nutrients already in the soil — fertilizing alone can’t overcome high pH
- Controls hydrangea bloom color — acidic soil produces blue blooms
- Apply before planting or to established plants — one cup per square yard
- A Stark Bro’s exclusive — formulated for the acid-loving plants we grow and sell
