@ Matt & Bob - I just read your most recent posts about white fly, aphids & other pests.
I can't say that I have experience with this but I've been learning a lot about micro-nutrients, microorganisms, and Brix meters. Basically if you provide what the plant needs in the correct proportions, your plants will create sugars that the insects can't digest. The will go somewhere else.
The Brix meter allows you to read the sugar level of the leaves and fruit. This lets you know how you are doing. With experience I'm told, you will even become so attuned to the needs of your plants that you will know what is out of balance.
As I learn more I will continue to add information and links this discussion or my blog where it is easier to consolidate information. But in the mean while I suggest looking into this.
Here's one place to start. It's an audio stream. http://www.wamc.org/post/alan-chartockin-conversation-dan-kittredge
Yep. This is exactly what I was talking about. I was told that if your plants are healthy they will "naturally" resist pests. I hadn't heard of the brix meter though. I will definitely look into this.
Thanks for the heads up!
Healthy plants might do ok despite some pest infestation, still produce and recover easily, but i doubt you will see real resistance. There are methods to help: natural predators, spraying with worm casting tea, soapy water etc. But just because you see bugs does not mean your plants are not at their best in terms of health.
It only seems to be the broccoli, which is weird. I went through today and removed any eggs that I saw. I may need to do a treatment of the water soap that I read about. I also noticed that the broccoli leaves have a slight yellow to them, I already ordered some cheleated iron (I dont know if I spelled that right). I'll add that when it arrives, though the other plants look green and healthy.
Matt, are the new leaves yellowing between the veins? Or are the old leaves yellowing between the veins? Or are the leaves, veins and all starting to yellow.? Each of those three scenarios are indicative to three different deficiencies...only one of which would be helped by adding iron. So a better description of the yellowing would help us to help you
I'm going to make a somewhat educated guess (since without a better description or a pic...or better yet, both...that's all it could be...a guess) and presume that your seeing some inter-venal chlorosis on the older leaves, and actually have a magnesium deficiency going on with the broccoli, and not an iron deficiency. This is assuming that your pH is in order (below neutral). I also say this because I'm assuming your system is new-ish (less than a year old) and because the brassica family (like broccoli) have somewhat heavy magnesium requirements...
As to the OP, sure. Healthy plants (like all animals and humans) will be more resistant to disease and pests, than deficient ones. But it's not a magic bullet or anything. Excess nitrogen coupled with 'not enough' of the other 12 plant essential elements (as is often the case with new AP systems) is just asking for pest problems...more so.
A little late to the conversation, but I have to agree with Pat & Vlad that even the healthiest plants can get infested, just like really healthy people can get infections. But, if other plants are around that are weaker, the pests will go to them first. You can also try growing plants that attract the pests and divert them away from your veggies. Then when the attractant plant is infested, you destroy the plant...or better, feed it to chickens. They love aphid infested vegetation. :)
In aquaponics we want to avoid soaps and oils, so teas from garlic, cayenne and cinnamon are helpful, as is milk and, in particular, worm tea.
Vlad, with a new system, Bob's PH is more than likely higher than neutral; very often here our tap water is 8.2 - 8.4. We normally have to lower it until the system is established and lowers it naturally. Would a high PH change your diagnosis?