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Monterey Lawn & Garden Bi-Carb Old Fashion Fungicide Concentrate, 4 oz.

Item #: 704618

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Bi-Carb Old Fashion Fungicide, 4 oz.

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Control powdery mildew the organic way. Similar to the baking soda Grandma used!

Potassium bicarbonate soluble powder for control of powdery mildew on roses, vegetables, grapes, fruit trees and ornamentals. Control powdery mildew the organic way. Similar to the baking soda Grandma used!

Bi-carb old fashioned fungicide is a fungicide containing microencapsulated potassium bicarbonate as the active ingredient. Bi-carb old fashioned fungicide is a contact fungicide, so direct contact with the fungus organism is required for control. Disrupts the potassium ion balance in the fungus cell, causing the cell walls to collapse.

Application Directions:

For residential use. Apply with a hand-held sprayer making sure to spray foliage thoroughly. Contact of the disease organisms is essential for control. Use a non-acidifying spreader/sticker such as Monterey's - Natures Own Spray Helper. In addition, users can also use a non-phytotoxic crop oil.


Brand Monterey Lawn & Garden
SKU 704618
Weight (lb.) 0.2
Width (in.) 2.3
Height (in.) 4.33
Length (in.) 2.3
Special Order Yes
Free Shipping No
Bug Type Fungus
Application Type Liquid
Product Type Insecticide
OMRI Certified Yes
Usage Area Outdoor
Concentration Concentrated
Concentration Ratio 4 tsp per 2 Gallons
Ingredient Base Organic Based

Monterey Lawn & Garden Bi-Carb Old Fashion Fungicide Concentrate, 4 oz. Questions & Answers

What is Bi-Carb Old Fashioned Fungicide?

Bi-Carb Old Fashioned Fungicide is a preventative and eradicant fungicide for the control of powdery mildew based on potassium bicarbonate. It is called "Old Fashioned" because if your grandmother wished to control powdery mildew on her roses she would mix up a solution of baking soda (sodium bicarbonate) and use it as a spray. In fact, many organic growers use this method today. We have replaced the sodium with potassium since it is safer on the plant and breaks down into an essential plant nutrient for the same results.

I see Bi-Carb Old Fashioned Fungicide has “OMRI Listed” logo on the label. What does this mean?

It means that this product is has been listed by the Organic Materials Review Institution as an organic product and can be used by certified organic growers as well as the general homeowner who wants an organic method of disease control.

What can I use Bi-Carb Old Fashioned Fungicide on?

There are numerous species on the label. Plants that are highly susceptible to getting powdery mildew are ornamentals such as roses, euonymus, and crape myrtles, vegetables such as squash, melons, cucumbers, pumpkins, peas, beans, beets, and Swiss chard. Small fruits and berries such as cranberries, strawberries and grapes. And fruit trees such as apple and pears.

How does Bi-Carb Old Fashioned Fungicide work?

It must be sprayed to come in contact with the powdery mildew fungus. It then disrupts the potassium balance in the cell wall causing them to collapse.

What rate do I use Bi-Carb Old Fashioned Fungicide?

Apply 4 teaspoons in 2 gallons of water and thoroughly cover the foliage. Once mixed with water it should be sprayed within 24 hours.

When should I start to apply Bi-Carb Old Fashioned Fungicide?

Make the first application at the first sign of powdery mildew. It is best to apply early before the mildew has become well established. Repeat at 7-10 day intervals until the disease is under control or the weather changes so it is unfavorable for the disease. You can apply on fruits and vegetables up to the day before harvest.

What precautions should I take?

A spreader sticker may be applied such as Monterey Nature’s Own Spray Helper to help make the product more rainfast. Thorough coverage is necessary for good disease control.

Shipping Info:

Ships Via FedEx/UPS

Shipment Restrictions -
This item cannot be shipped to the following locations: AK, AR, DC, ID, ND, NE, OK, WY
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