Mycorrhizae and Trichoderma ----learning never stops

[Chuck]

I have/had a problem with the yellowing on my brassicas. Some sort of chlorosis, so I got in touch with headfullofbees to see what he had to say about it. He suggested that I go pull up the worst of the affected plants and inspect the root system which I immediately did. Low and behold it had very robust and healthy root system, really big and thick for a plant that has been in the ground for less then 3 weeks. So, I get back back to Bees, tell him about them and attribute these great roots to mycorrhizae of which I always add a very small amount when I water. To my dismay he said that mycorrhizae is not compatible with brassicas. So, being the skeptic I am, I did some online research and found out he is absolutely correct. Then I asked myself why. Why are these roots so big? I did some more online looking and I am sure that I have found the answer and the answer is trichoderma.. It is another beneficial fungi whose favorite growing medium is whole ground cornmeal. The data that I read said that trichoderma attaches itself to the root systems of (young) brassica plants and that these same young plants exude a sugar that the trichoderma feeds on. This fungi protects the young roots from other harmful soil borne fungi AND bacteria. Plus it also helps in the uptake of nutrients almost like mycorrhizae does. And this is, I think, why my brassica had such robust roots. But back to the original problem of yellowing leaves. We are pretty sure it started with the unseasonably cold temps and howling winds we had here last week. But just in case I am going to double up on NPK for a short while.

I thought I would also describe my potting process as it will also help explain why the roots were so big. I always start out with a 5 gallon bucket of mix because I usually pot up a bunch of plants whether they be tomatoes or peppers or whatever that will be transplanted later. I fill a 5 gallon bucket not quite full of a 50/50 mix of potting soil and compost. My potting soil is basically super composted compost, just about the dirt stage and the compost is just my basic 1 year old compost. I dump this into a wheelbarrow and start mixing it up with a shovel. I add in 6 tsp of mycorrhizae and 1 gallon of whole ground corn meal. If I have any left over fertilizer (I usually don't) I will dump in a little of that too. You don't want to put seedlings in a high nutrient environment but I always thought a little wouldn't hurt. I also add about a quart of greensand and really mix it up. I then pot the seedlings up in whatever containers I have. When I a full flat of them potted up I mix 2 oz of liquid seaween per gallon of water and put 2 or 3 gallons in the wheelbarrow. In my small wheelbarrow 3 gallons of water comes up to not quite the top of the flat the seedlings are in and I really soak them. When there is water standing in the seedling containers I take them out and let them drain back into the wheelbarrow. If there is any liquid left after the potting process I dump it into the compost pile. I never water the seedlings from the top down, always from the bottom up unless it rains. I also only water with straight basic compost tea with 2 OZ of molasses added and I can't remember the last time I lost a seedling

 

[Chuck]

I have/had a problem with the yellowing on my brassicas. Some sort of chlorosis, so I got in touch with headfullofbees to see what he had to say about it. He suggested that I go pull up the worst of the affected plants and inspect the root system which I immediately did. Low and behold it had very robust and healthy root system, really big and thick for a plant that has been in the ground for less then 3 weeks. So, I get back back to Bees, tell him about them and attribute these great roots to mycorrhizae of which I always add a very small amount when I water. To my dismay he said that mycorrhizae is not compatible with brassicas. So, being the skeptic I am, I did some online research and found out he is absolutely correct. Then I asked myself why. Why are these roots so big? I did some more online looking and I am sure that I have found the answer and the answer is trichoderma.. It is another beneficial fungi whose favorite growing medium is whole ground cornmeal. The data that I read said that trichoderma attaches itself to the root systems of (young) brassica plants and that these same young plants exude a sugar that the trichoderma feeds on. This fungi protects the young roots from other harmful soil borne fungi AND bacteria. Plus it also helps in the uptake of nutrients almost like mycorrhizae does. And this is, I think, why my brassica had such robust roots. But back to the original problem of yellowing leaves. We are pretty sure it started with the unseasonably cold temps and howling winds we had here last week. But just in case I am going to double up on NPK for a short while.

I thought I would also describe my potting process as it will also help explain why the roots were so big. I always start out with a 5 gallon bucket of mix because I usually pot up a bunch of plants whether they be tomatoes or peppers or whatever that will be transplanted later. I fill a 5 gallon bucket not quite full of a 50/50 mix of potting soil and compost. My potting soil is basically super composted compost, just about the dirt stage and the compost is just my basic 1 year old compost. I dump this into a wheelbarrow and start mixing it up with a shovel. I add in 6 tsp of mycorrhizae and 1 gallon of whole ground corn meal. If I have any left over fertilizer (I usually don't) I will dump in a little of that too. You don't want to put seedlings in a high nutrient environment but I always thought a little wouldn't hurt. I also add about a quart of greensand and really mix it up. I then pot the seedlings up in whatever containers I have. When I a full flat of them potted up I mix 2 oz of liquid seaween per gallon of water and put 2 or 3 gallons in the wheelbarrow. In my small wheelbarrow 3 gallons of water comes up to not quite the top of the flat the seedlings are in and I really soak them. When there is water standing in the seedling containers I take them out and let them drain back into the wheelbarrow. If there is any liquid left after the potting process I dump it into the compost pile. I never water the seedlings from the top down, always from the bottom up unless it rains. I also only water with straight basic compost tea with 2 OZ of molasses added and I can't remember the last time I lost a seedling

My bad, I forgot to show what was wrong. Here are some pics. The first 3 are cauliflower. The nest 2 are brussel sprouts and the last is a brocolli. You might see some holes and pieces of the leaves missing but those were from cabbage loupers and grasshoppers which are now ancient history

 

[headfullofbees]

Chuck, I'd remove all the damaged leaves; they are dead and of no further use to you.
This is likely to stimulate new growth, and be less likely to encourage nasties.
The newer leaves will be much hardier.

 

[Chuck]

Chuck, I'd remove all the damaged leaves; they are dead and of no further use to you.
This is likely to stimulate new growth, and be less likely to encourage nasties.
The newer leaves will be much hardier.

I am going to do that today. Some of the lesser damaged leaves appear to be growing out of it and the most damaged have turned brown and shriveled up.

 

[Pat]

I agree removing the the damaged leaves with help stimulate growth in the plants. I regularly pinch back plants as they start to get stringy and want the plant to bush out a little more.

 

[headfullofbees]

In New Zealand, scientists have been experimenting with trichoderma in the fight against clubroot.

Trichoderma also help with damping off, so that's another reason your success rate with seedlings is so good.

 

[Chuck]

In New Zealand, scientists have been experimenting with trichoderma in the fight against clubroot.

Trichoderma also help with damping off, so that's another reason your success rate with seedlings is so good.

Yep, that is why I put so much cornmeal in my potting mix, to stop damping off. I also add a handful to my compost tea when it gets warm. It doesn't completely stop early blight on my tomatoes but it slows it down considerably, enough to not have my crop affected, especially on the indeterminate varieties. And don't forget that it is a cure for toenail fungus and athletes foot too.

From what I understand about it, it really doesn't have anything to do with nutrition in a plant. What it does is act like a rich mans bodyguard, it either repels or kills the bad guy, in this case harmful fungi and sometimes bacteria, although I don't see how a fungus does much against a bacteria. Anyway, it works and that is what matters. I will leave the science to the scientists. I'm just a poor old redneck country boy, what do I know?

 

[headfullofbees]

Plus, it seems to trigger the plant's defence responses, (With both mycorrhiza and trichoderma, they invade the plant's root systems, so the plant believes it's being attacked.) so that, metaphorically speaking, the port-cullis is up before the real baddies attack.

 

[Chuck]

Plus, it seems to trigger the plant's defence responses, (With both mycorrhiza and trichoderma, they invade the plant's root systems, so the plant believes it's being attacked.) so that, metaphorically speaking, the port-cullis is up before the real baddies attack.

While I was looking at the data about it there was a pic taken with an electron microscope or something similar. It showed a plants thread roots with and without trichoderma being present. When it was present it appeared that the roots had some sort of growth on them that slightly resembled fish scales and apparently these fish scale things acted as a shield against the bad guys so that they couldn't get to the roots themselves. And also from what I could understand from all the scientific mumbo jumbo is that there are different kinds of trichoderma that affect different types of plants, like between trees and grasses or brassica and tomatoes