Bonide Rot-Stop Tomato Blossom End Rot, 16 oz – Calcium-Deficiency Garden Fertilizer

Protect tomato fruit with calcium-focused care

Bonide Rot-Stop Tomato Blossom End Rot is a 16 oz concentrate designed to help address calcium deficiency that can lead to blossom end rot on tomatoes and other vegetables. The formula supports developing fruit and foliage, usable indoors or outdoors across different conditions.

When weather or growth stages stress plants—heavy rain, rapid growth, or fruit set—extra calcium can be helpful. This Rot-Stop concentrate provides a readily available source of calcium through a calcium chloride-based active ingredient, so you can tailor feeding to the season without overhauling your routine.

What it does for your garden

• Corrects calcium deficiency by delivering calcium to developing fruit and leaves, supporting healthy growth.
• Calcium chloride provides the nutritional calcium that's the main active ingredient.
• Versatile for tomatoes and other crops, including cucumbers, melons, and peppers, making it a multi-crop option.
• Easy to apply—instantly mixes with water and works with hose-end sprayers or tank sprayers.
• Functions as a foliar supplement to a regular fertilization plan, not as a standalone nutrient source.

How to use

• Mix with water and apply using a hose-end sprayer or a compatible tank sprayer.
• Spray foliage and developing fruit to the point of run-off for even coverage.
• Apply after periods of heavy rainfall or during rapid plant growth when fruit is forming.
• Always read the label directions and use as part of a balanced fertilization program.

Why choose Bonide

Bonide has been trusted since 1926 to provide practical lawn and garden solutions. Rot-Stop is designed to complement your care routine, supporting fruit development indoors and outdoors as part of a complete feeding strategy.