BioWorks - BotryStop WP - 12 lbs

BotryStop WP Biofungicide for Gray Mold Prevention

Live spores of Ulocladium oudemansii strain U3 make up 45% of this BioWorks wettable powder. The label guarantees at least 80 million colony forming units in every gram. U3 is a saprophytic fungus that grows on dead and dying plant tissue and leaves healthy tissue alone. Spent blossoms, petal fall and senescing leaves are where Botrytis cinerea usually breaks in. Once U3 spores settle there, they germinate, colonize the tissue and can sporulate again on fresh debris. That leaves Botrytis and Sclerotinia with nothing to feed on and no space to grow. With this competitive mode of action, the label calls resistance highly unlikely. Bedding plants and nursery ornamentals are labeled for gray mold and Xanthomonas. Berries, vegetables, tree fruit, edible flowers and hemp are covered as well. Re-entry is 4 hours, and applications can run up until harvest. It is OMRI Listed, and the Warning signal word reflects temporary eye irritation from the powder. The 12 lb bag fits mid-size greenhouses and berry blocks sprayed through the season.

Botrytis Control on a Preventative Schedule

Good botrytis control starts before symptoms, when cool, humid weather sets in or bloom begins. The label rate is 2 to 4 lb per acre, repeated every 7 to 10 days. In hand sprayers, use about 1.1 tablespoons per gallon at the low rate and 2 tablespoons at the high rate. Slurry the powder in a bucket of water first, then pour it into a half-full tank. Add a non-ionic surfactant and keep the agitator running throughout. The finest droplets give the best coverage with the least residue. Spray to full wetness without runoff, and use the mix the same day. Keep it out of irrigation systems entirely. Pair it with no more than one other product, after a jar test. A cool, dry spot at or below 68°F protects the spores. Expect about a year of shelf life at room temperature, or 18 months refrigerated.

Key Features

• Live U3 Spores: 45% Ulocladium oudemansii with at least 8 x 10⁷ CFU per gram.
• Occupies Dead Tissue: Claims spent blossoms and dying leaves before Botrytis does.
• Labeled Targets: Gray mold, Sclerotinia, Monilinia blossom blight and Xanthomonas.
• Gentle on Live Tissue: Grows only on dead and senescing plant material.
• Low Resistance Risk: Competition rather than chemistry drives control.
• 4-Hour REI: Crews can return the same shift.
• OMRI Listed: Approved for certified organic production.
• Hand Sprayer Rates: BioWorks small-volume chart gives tablespoon rates per gallon.

Technical Specifications