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Actinovate helps prevent black spot on roses and many diseases that affect tomatoes.

Introducing Actinovate

A Safe, Effective and Organic Way to Control Plant Diseases, Including Late Blight

Good soil

Actinovate contains a naturally occurring bacterium called Streptomyces lydicus, which is responsible for the distinct "earthy" odor we associate with moist, healthy soil.


Foliar diseases make plants unsightly and can reduce yield. Actinovate helps control many of the most common diseases that attack garden plants.

By Suzanne DeJohn

Actinovate® sounds too good to be true. A safe, effective organic pesticide that controls all sorts of plant diseases, from root rots to leaf blights? But it is true. Actinovate contains a patented beneficial microbe that suppresses and helps control a wide range of diseases, including black spot on roses and the late-blight fungus that devastated tomato crops a few years ago.

Using beneficial microbes to manage plant pests isn't something new; farmers and gardeners have long been harnessing this power to control pest problems. By adding compost and other organic matter to soil you're encouraging a healthy soil ecosystem in which beneficial microbes keep pests microbes in check. And when a pest problem arises, microbes can come to the rescue in the form of milky spore, Bt and beneficial nematodes, all of which have been widely used for many years.

The active ingredient in Actinovate is a naturally occurring bacterium called Streptomyces lydicus strain WYEC 108. There are more than 500 species of streptomyces bacteria and they're generally found in rich soils that contain decaying organic matter — they're responsible for the distinct "earthy" odor we associate with moist, healthy soil.

The beneficial properties of various streptomyces bacteria have been known for years and have been used in naturally derived antibiotics, including its namesake, streptomycin. The streptomyces bacteria species in Actinovate provides a similar service to plants by colonizing the roots and protecting plants from harmful fungi. Applied to the foliage, it helps control leaf diseases.

Best of all, Actinovate is safe, unlike synthetic fungicides, many of which are under increasing scrutiny as possible carcinogens. The US Environmental Protection Agency has declared Actinovate safe for us and for the environment, adding that "the use of this bacterium in pesticide products will not increase the exposure of humans beyond normal background levels."

Related Information

Watch Out for Late Blight

Tomatoes are susceptible to many diseases and it can be challenging to determine the culprit. Late blight, the disease that decimated crops in 2009, has made just a few rare appearances so far in 2011, but it pays to be on the lookout. More information:

According to the manufacturer, Natural Industries, Actinovate:

  • Stops lawn diseases, including brown patch (Rhizoctonia), dollarspot (Sclerotinia), take-all patch (Gaeumannomyces graminis) and pythium blights.
  • Prevents root diseases in ornamentals and vegetables, including pythium, phytophthora, rhizoctonia, verticillium and fusarium.
  • Attacks foliar diseases, including powdery mildew, downy mildew, grey mold (Botrytis), fire blight (Erwinia), leaf spots and rusts and black spot (Diplocarpon rosae).

One 20-gram packet of Actinovate treats 200 plants. For optimal results, use Actinovate as a soil drench at planting time, and then as a foliar spray every 7 days. The packet label offers details on dilution rates, application tips and other helpful information; be sure to follow these instructions.

Vermonter Suzanne DeJohn has been gardening and writing about gardening for more than 20 years.

Last updated: 1/4/17

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