How to Identify and Manage Downy Mildew in Lettuce

In greenhouses, followers can additional decrease humidity and stop extended leaf wetness.

Bodily

If the illness is caught early and restricted to the outer leaves, eradicating the symptomatic tissue can gradual its unfold. In some instances, this can be sufficient to salvage the crop.

Nevertheless, leaf removing alone shouldn’t be a remedy. Mix it with preventative measures or natural remedies to cut back the prospect of reinfection.

Organic

Therapy works greatest once you use it preventatively or on the primary signal. As soon as the illness advances, your choices are restricted.

The next merchandise are extremely efficient as preventatives, however received’t work so properly if the illness is already established.

At all times comply with label instructions, as producers present particular protocols for focusing on this illness.

Streptomyces lydicus WYEC 108 is a naturally occurring bacterium that suppresses fungi and oomycetes.

It’s the energetic ingredient in merchandise like Actinovate AG that may assist cease downy mildew in its tracks.

Actinovate AG

You’ll find 18-ounce baggage of Actinovate AG at Arbico Organics.

Another choice is Bacillus subtilis pressure QST 713. This useful bacterium colonizes plant surfaces and outcompetes pathogens with out harming the host.

You’ll find it in merchandise like Serenade ASO.

Serenade ASO

Serenade ASO is accessible at Arbico Organics.

Natural Fungicides

Like organic remedies, natural fungicides work greatest as preventatives. As soon as downy mildew is current, it’s a lot more durable to cease or management, however that doesn’t imply you shouldn’t attempt.

Should you see the illness on one plant, deal with your entire lettuces, no matter whether or not they’re symptomatic or not.

You can too alternate an natural herbicide with a biofungicide as long as you comply with the producer’s instructions rigorously.

Copper is a well known fungicide that has been used for many years to suppress fungal and oomycete ailments.

It damages cell partitions and causes the contents to leak out, killing the pathogen.

Monterey Liquid Copper Fungicide

You’ll find Monterey’s Liquid Copper obtainable at Arbico Organics.

Sulfur is one other tried-and-true choice. Utilized each two weeks, it may well assist suppress outbreaks alongside copper sprays.

Bonide Sulfur Fungicide

You’ll find Bonide Sulfur Fungicide obtainable from Arbico Organics.

Thyme oil comprises thymol, which assaults the cell partitions of pathogens, killing them. It’s efficient at treating downy mildew if used on the first signal of bother.

Guarda

You’ll find Guarda, which harnesses thymol, obtainable at Arbico Organics in two-and-a-half-gallon containers.

Potassium bicarbonate prevents and suppresses illness by disrupting fungal cell partitions. It’s efficient towards downy mildew in addition to powdery mildew, leaf spots, and botrytis.

Milstop SP

Milstop SP is made utilizing potassium bicarbonate and is accessible at Arbico Organics.

Citric acid acts each systemically and on plant surfaces. It may be utilized repeatedly and supplies safety towards a number of ailments, together with downy mildew.

Plus, you’ll be able to spray it as usually as wanted. Search for merchandise like Procidic, which comprises citric acid.

Procidic

Procidic is accessible at Arbico Organics in 32-ounce ready-to-use bottles, or 16-ounce and gallon concentrates. 

Along with these merchandise, hydrogen dioxide can be an efficient remedy choice, usually utilized in rotation with different merchandise.

Chemical Management

For house gardeners, there aren’t any chemical fungicides that persistently outperform the natural choices listed above.

Stick to these advisable above and be sure you rotate via just a few completely different ones to forestall the oomycetes from growing resistance.

Out, Rattling Spot!

Downy mildew is distressingly frequent and frustratingly resilient. I hope you by no means should take care of it, however don’t despair should you do.

Even probably the most skilled growers encounter it occasionally.

What sort of signs are you seeing? Are you having bother figuring out what you’re coping with? Hit us up within the feedback part beneath and we’ll see how we will help.

And for extra details about frequent lettuce issues, have a learn of those guides subsequent:

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