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ladybug eating aphids
What do you do when organic methods fail to correct a problem?

Question details

A question to organic gardeners: say, You face a pest or disease You are unable to control by organic, natural means. Do You switch to chemical warfare "just once" or do You accept the loss?

Gooq question Antonis: I put it to KGI's facebook fans and had the following feedback: -Try something else. Keep learning. Keep trying. -Accept the loss. I know it's something that I did not act on early enough or was oblivious to. My fault and I choose not to punish the environment for it but learn and move on. I guess gardening is a little like parenting for me. LOL -Definitely a teachable moment! Never chemical warfare. Look for ways nature might help. -Try, try again, then give up. Three years of late blight in my tomatoes. That's it - I tell myself I'll just buy my tomatoes from a farmer who doesn't get hit this year. But, who knows, I'll probably end up planting a few, just in case... -Research like a madwoman until I find an answer. Which is how I learned to control Brassica aphids. -I write it off, hope it won't happen again next year and possibly switch to a variety less prone to the pest or disease. -I have tried both and decided that while chemicals solve the problem of the moment they cause even more problems over time. So... I use it as an excuse to do a bit more research and experimentation then pass what I have learned along to others so maybe they won't have those problems.
So far, the only time I've had to use chemical warfare is on our peach tree. It had peach tree borers and these will kill the tree. They got the other one. I've had to apply chemicals (Sevin), but very judiciously, and only on the lower portion of the trunk, painting it on with a brush, and then only after the blossoms were gone so no bees would have reason to be near the tree. I know of no other solution to the problem. I've never needed chemicals for the vegetable garden. You will probably need to accept some loss, how much is up to you. One third would not be too much. We are not marketing vegetables, so no big deal. And often, the crops are perfectly edible though not marketable. Row covers are very helpful on greens, cabbage, spinach, etc. If you use it over cucumbers, remember to remove it when the plants begin to blossom so proper pollination can take place. Companion planting is very helpful . . . mix it up to confuse them. I credit this with almost eliminating any bug issue. I plant lots of marigolds from seed and plant them among the various crops all over the garden . . . and I plant onions throughout. I once planted two varieties of kale, side by side. The bugs liked one and not the other . . . so I harvested one and conceded the other. After a couple of weeks they gave it back to me, they simply left . . . so I took it over again. If you use overhead watering, I would suggest using soaker hoses to keep the leaves from getting wet. I hope these few comments are helpful. Generally, with sound organic practices, pests are not a big problem. Good luck!
Of course,trees are a different story.With annuals You have the luxury of a new chance every season.Your application at the peach tree sounds very wise and careful.Thank You very much for the detailed answer ! Greetings,antonis.
Work to achieve a healthy soil. Add lots of compost, beneficial bacteria and fungi. Unhealthy plants are the first and most attacked by harmful pests. Rotate crop areas if possible. You may even have to skip planting a certain crop for a while. Just try not to succumb to the chemical giants' lobby. Their way creates more problems than they solve, but it seems you know that. By the way. that is a marvelous photograph. Is it your creation? Stay natural, David
The truth is that a friend helped out with the picture;he deserves the credit for it,not me.Thank You very much for taking the time,David.Greetings,antonis
Sometimes natural solutions take time. The theory is *when there is a pest prey the predator will show up.* One year thrips appeared & rolled all the leaves on my two beautiful, already 5" caliper Green Gage Plum trees. I researched sprays & decided I just couldn't spray those toxins. So the Plums looked brownish-ragged all season & had a measly crop. The next year & all following years they were back to normal beauty & heavy production. I don't even really know what predator appeared. I did not see any changes in the insects & birds in the garden landscape.
Thank You very much,everybody!I agree with everything You have said.I may add,one fair method I have started to apply this year is spraying compost tea once a week,a preventive measure.So far everything looks fine, but time will tell when it gets really hot later in summer and our notorious spider mites show up. So,not a single voice in favour of chemicals.May be,different minded people gather somewhere else. In my view,too,if a dispute with nature cannot be solved by fair means it is wise to at least keep it at argument level.Arguments turn easier into friendship than fights do. Greetings to Everybody!
William Brinton, the compost scientist at Woods End Laboratories in Maine, writes that Canola oil is an adjuvant that enhances the beneficial ingredients in foliar compost tea & the surface microbial life on plants. These days you would have to look for organic Canola oil, since ~80% of Canola oil is GE/RR. I would use ~ 1 tablespoon per quart of spray. The additional *horticultural oil* effect might help against spider mites.
Thanks a lot,Jessica! This sounds like a good idea.I wonder if linseed oil would do,too.Greetings,antonis.
I think it would depend on the viscosity texture of Linseed oil, which I haven't handled for some time - since I used it to put the final gloss on furniture I was refinishing. Linseed oil will *set up* a hard finish in a way that food-grade oils do not. Canola oil is less viscous than Olive oil. And the *horticultural oil* you can buy is even lighter. If you try Linseed, I would mix it with warmed liquid to spray ... let us know! :-)
Linseed oil is also one of my favorite wood finishes,especially on weathering wood.For this usually,and best, "boiled" i.e. dehydrated oil is used; for exactly the reason You mentioned.For spraying the garden I use natural and unmodified pharmaceutical / food grade linseed oil.I have done already one round and it seemed to dilute and spray fine.The composition of linseed oil is rather similar to canola,I think.Also, I have some readily on the shelf and do not need to go buy it and worry about it being GM....
Hi, This is a great place to visit for information, is there a recipe for this compost tea spray. I am in northern california, on the bayside, southern marin. I had 3 wonderful tomato years, the last 2 have been bad, cold nights not very hot days, least year i got the blight, nothing helped, did get some tomato sauce. I just love my veggie garden i look forward to it all year, I am giving it another try, I would love to try your spray, i have nothing to lose except the costs involved. Thank you
Kalos tin! Compost tea. If You google that You will get a fairly good idea of the concept. Here it definitely would deserve a separate thread. What I do is having water,free of chlorine,seep through compost (at least semi-ripe) and collect the runoff. The resulting brown soup I use instantly and undiluted for spraying and watering once a week. Brewing, propagating it ,I omit; whether this is to be named compost tea or not ,is open to discussion. Cost: 0,00 $/Euro/Piaster/Yen/Rupees/Pounds. I don't expect this to be a magic cure but rather a general strengthening of the plants,similar to using good quality food supplements and superfoods to humans. Also, I have been doing this for six weeks only and it's too early to make any big statements. The oil addition suggested by Jessica above can be expected to impact bugs only,while blight is a fungal issue if I'm not mistaken. BUT: if Your tomatoes have been growing at the same spot every year then changing the spot will do more good than any spray can. If You have rotated Your tomatoes and still get the blight You could consider post an according question. Try to put it as specific as possible so you will get better answers. Greetings, antonis.
Okay, here is an update on compost tea or - more accurately - compost extract as I make it. Throughout spring and well into summer I foliar-sprayed the garden about once a week and watered often with it, watering was continued for the rest of the summer. The result: no pest or disease activity to speak of. The downside: all these appear now to have been secondary problems, the real issue - unaffected by compost extract - seems to be most of the plants having difficulty in taking up nutrients as soon as the soil heats up too much: what first looks like K or Mg deficiency develops into scorching the plants from the lower branches up until they finally die. Fertilizing does not help. Ergo: I had about the same failures as last year - but at least I know now what it is and can adjust. Despite that the overall result is still quite bearable: it looks like the 50kg/100+lbs per annum and off 10 sq m/110 sq ft will be hit this year.
The answers are all in the soil. In nature, only the weak are attacked by pests and disease. In our gardens we often force plants to grow, using unnatural amounts of fertiliser, whether it be chemical or organic. Consequently imbalance occurs and plants cannot access what they need because they are suffocated with too much nitrogen, for example, making plants weak and subject to attack. Seek knowledge about your soil and soil health in general. Use kelp if possible. Try to avoid one off solutions, as you will spend a lot of money and never achieve total success. Sorry this is not more specific but life never is that easy!
Yes,You are perfectly right.However,what I have in mind are those problems ,which occur regionally due to special,extreme, local conditions and effect all gardens more or less.In our case this is spider mites and some diseases they carry, due to excessive heat during June to September.The best solution to this would be to grow almost nothing during this period, as nature does observably.But this is not a real option for most of us and so we enter bargaining with nature.The subject is how far we will go in this attempt and by which means. Of course, none of us intents to write scientific papers here, but all the various inputs, tips and views do add up to some very valuable "cloud papers". Thank You very much for taking the time.
Hi antonis - thanks for the info above, we don't see the lighter food-grade Linseed oil here, so I wasn't aware of it. A spray with a horticultural oil added might be good for fungal blight. For years I have used a light oil spray to cure powdery mildew in various plantings. The Aster Laevis I use for my profile photo is very susceptible to pm & I have used lots of it in big gardens, since it blooms until the snow flies & makes a great, late bee plant. Oil spray would work on berry bushes that get mildew as well, without applying a toxin you don't want to eat. One spray cures it & it may have to be repeated a couple of times during the season.
Thanks for pointing this out,Jessica!I hope,@yiayia reads it, too.When spraying diluted milk failed to have any effect on what I believe to have been fungal blight at my zucchini last year,I simply concluded that fat/oil won't do any good.Some sources say that oil sprays should be applied in cloudy weather only,in order to work.In summer,cloudy skies we have hardly ever here....Also,having that part of the garden planted definitely too densely surely contributed,to say at least,to the problem.This is a real temptation when You have excellent soil in your containers,but not much space.......
As we become familiar with the new kgi website - there is quite a lot of prior discussion about *compost tea* in SEARCH.
Yes,but somehow I'm unable to extract a simple and foolproof silver bullet&magical solution.Probably,I'm asking too much for.....So,I'm back to experimenting.However,when going through literature I often get new ideas to combine with what I'm already doing and such, things are kept interesting........
I'll check to see if the thread I remember is still in SEARCH. And here we have an excellent arborist I've worked with who has been making his own *secret ingredient* tea for years. Now he sells it through our Sustainability Center. I'll see if I can catch up with him & ask a few questions. I too am for *open science*! :-)
These are the two links that came to mind ...
Hello, In the Czech Republic they sell liquid used for improving plants´ health. It is also good for curing or preventing mildew and blight. It consists of rape plant oil (55percent) and lecitin (2percent). You make 0,5 to 3 percent solution with water and add about 15 drops of washing liquid per liter (to make the plant leaves thoroughly wet). Should not spray when the temperature is hot or the sun is strong (do it in the evening or when cloudy). This year I am going to try it for the first time. Do you know also something like Pythium mushroom? It is supposed to coexist with the plant and make it stronger too.
Very interesting for multiple reasons! (1) Do you live in the Czech Republic? (2) The preparation you describe is what I have used for many years to stop Powdery Mildew on plants such as Aster Laevis, seen in my profile photo, or sometimes currant bushes. The oil simply interrupts the PM-fungal-parasite connection with the host plant. This treatment is inexpensive & effective. (3) William Brinton, the compost scientist at Woods End Labs in Maine, USA, has noted in a paper that Canola oil is a natural *adjuvant* & when applied in such plant sprays it enhances the health & interactions of beneficial bacteria on the plants. (4) I noted then that *most* north American Canola oil is now GMO & as a commodity field crop, it carries the RR Roundup Ready gene, which is from a bacteria. We know from historic experience with vaccine manufacture & use that taking in a foreign bacteria stimulates an ongoing human immune system reaction. (5) The other day I searched online for *organic source for Canola oil.* One USA organic product manufacturer met there has written me that they have to source organic Canola oil from the Netherlands because north & south American Canola is either GMO or contaminated. Further, the advancement of GMO contamination is such that they have to test each batch afresh to ensure that it is GMO-free. (6) I wonder if you know the status of GMO regulation and/or labeling in the Czech Republic, with respect to their Canola?



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