Does anybody have experience with it? I am going to kill my horseradish bed next spring as it is infected with terrible root rot. I found today that most possible reason is Fusarium oxysporum and Fusarium commune. The nasty thing lives in soil, but I can’t afford to just abandon this spot of my garden - not enough space to lose any. I am looking for soil fungicide I could use to clear up the soil. Will RootShield® Home & Garden do the job? It is pretty expensive ($22 for 4 oz, rate of use 3 tbs per gallon per 25sq foot, but I expect I will need more to drench the soil )
Which version are you considering?
I was looking at this: Rootshield Home & Garden - Control Soil Borne Diseases for Ornamentals, Flowers, and Vegetables
All others start with one pound package and cost above $118 
Though I see a difference now - the one that is more expensive has two ingredients, not one. (RootShield® PLUS + WP). I guess I will put it on my birthday gift list.
On the manufacturer’s site you’ll find a description of how the product works. I don’t think it fits your purpose.
Yes, I checked it already. I see it is listed as soil drench, why do you think it wouldn’t it work?
From the manufacturer:
- Grows on roots “shielding” them against root damaging fungi
- Releases enzymes that dissolve the cell wall of many fungal pathogens
- Promotes a healthier root system increasing root mass potential
- One application provides up to 12 weeks of protection
My approach would be a soil test for deficiencies in zinc, copper, and other metal electrolytes.
Did you consider solarization?
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Does deficiency of metal electrolytes promote fungus infestation or could cause the root rot?
The bed is about 4 feet tall on one side and shallow on other side. It is a former spot of “junk” compost, where I stored all the garden derbies before I discovered our town has yard waste collection all summer long. So I am not sure I can really "solarize " it that deep, keeping in mind there is 4 feet of infected fertile soil. The location is not that premium as well, it only has sun from sunrise til about 2 PM. My plan was to remove all the horseradish root I can, drench the soil with something and plant some potatoes there keeping in mind that horseradish will continue to grow and I will have to deal with it for few years.
I think what you’re thinking of is fumigation
But a lot of such products are no longer available, or not to unlicensed growers
I know that whenever I found a likely nematocide on sites like Arbico, it turned out to be prohibited in my state
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I read here and here that one proposed method is to lime the soil to raise its pH to about 6.5-7.
The second link also includes a list of fungicides for soil fumigation and drenching. They does not sound like something I would want on my vegetables.
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How about replacing the soil? That might be a viable option for a small bed.
I was thinking about it, but it is a lot of soil, it is much deeper than it has to be, I can use something like wood to fill deep side, but i would need to dispose large amount of existing soil and I am not sure where - it has to be removed by buckets and carried up the stairs, and then taken away somewhere… Very big task…
Many fungi and anaerobic bacteria thrive in such environments.
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I’d stick with resistant vegetable species, maybe plant through ground cover to take care of the horseradish. Beans, peas, carrots, celery, lettuce, sweet potatoes, corn, sunflowers, asparagus are all supposed to be resistant or immune.
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I suppose you could look at it that way, although what’s happening is the native fungi don’t like to host on those species.
strange, this is from wiki:
The fungal pathogen Fusarium oxysporum affects a wide variety of hosts of any age. Tomato, tobacco, legumes, cucurbits, sweet potatoes and banana are a few of the most susceptible plants, but it also infects other herbaceous plants
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I Googled “fusarium resistant vegetables” and clicked on the first link without looking, Google gave me this article about verticillium resistant plants instead. Sorry about that. http://depts.washington.edu/hortlib/resources/ucdavis_verticillium.pdf
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Yes, I searched too and saw it. In fact I didn’t find any lists for resistant plants for fusarium. I know some hybrids have some resistance but not to all the strains. I guess it is one nasty one I have on my hands… I think I will try clean the horseradish as early as possible, may be even in winter - soil is still not frozen for us. In early spring i will cover the area with plastic to warm up soil and use RootShield to deep potato tubers before planting, also will drench the soil and plant early potato there for summer crop. If it wouldn’t grow - I will not loose anything, as I do have (or at least should have) extra tubers for this. After potatoes are done, I will use plastic again in order to heat the soil for the the rest of the summer. And see what happen.
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I dug out a horseradish root once and when I finally got it out I almost needed a ladder out of the hole.
I’d be a little concerned that the horseradish might be a source of reinfection, so I’d want to be as thorough as I could be in getting it out. But maybe it doesn’t work that way- I honestly don’t know.