Can actinovate stunt seedling growth?
 

First off, let me say that I use Actinovate regularly, love the product, and recommend it to others all the time. I am not condemning it in any way.

On to the topic at hand. I typically water my seedlings with SeaCom PGR, fish fertilizer, and some EM1 bacteria mixed in and this works quite well. This year, on a few of the seeds that were started later than others, I added in some actinovate into the mix I just described and have been watering the seedlings with it. The seedlings that received this treatment have basically stopped growing and the leaves have become purple (the tops are purple, not the bottoms which could indicate phosphorous deficiency).

My question is, could actinovate have cultivated the young seedlings roots so well that it may be inhibiting nutrient uptake? I should have used the actinovate at reduced rates but did the regular 1tsp/2gallons. Any thoughts?

I can't say about actinovate specifically, but I can say that as a general rule, it is very common for a slight delay right at the beginning when using various organic methods that include various micro-organisms. That purple is also very common. They should grow out of it fairly quickly. I see the purple as a good thing. It is a sign that plants are producing hardy growth instead of luxurious, but easily killed growth.

Most cases it is a symbiotic relationship. That means right at first the micro-organisms colonize the plants and the plants actually are responsible for feeding themselves AND the micro-organisms. Later the beneficial micro-organisms repay that debt by supply the plant what it needs. So what you described is actually a common occurrence. It is also why most people start seeds in sterile soil-less potting mixes, and don't add micro-organisms until the seedlings are larger and more well developed. There are others though that start them right off from the beginning with beneficial micro-organisms.

I guess it is up to you to figure out what works best for you long term. One bit of advise though; either start them right off from seed with the micros, or wait till they are very well developed to do it. The middle ground of doing it when the seedlings are small is the worst option. I personally wait until a week before I start hardening them off for going in the garden. Then I hit them one more time as I transplant.

Yep, there is natural competition between plants and microbes for nutrients, especially in a newly introduced growing colony. Bacteria are greedy little buggers and hoard great quantities of nutrients in the soil especially Nitrogen which they are the primary sinks for in soil. That's a good thing since that prevents nutrient leaching. When they themselves die or consumed by predators, that cycles nutrients back in the soil in plant available forms.

You don't need to add a lot of bacteria to a pot with a seedling, one small application is enough, they multiply rapidly. Adding to much just creates too many bacteria competing for too little resources. If you add EM's at seed germination, it's better to introduce a broad spectrum of species instead of one. That way you don't have one species dominating and the seedling gets the benefits of the various growth promoting metabolites the different critters produce.

So was this a one time application to established seedlings? How old are the seedlings?

Ami

I've never experienced that with actinovate.

I don't recall the exact age of the seedlings since these seeds were started later than my main batch but I think they were around 3 weeks old. They were primarily peppers (although some tomatoes show similar signs) and were about 2" tall at the time.

The ones that show it the worst still have purple leaves and have all but stopped growing. They have probably put on 1/4 inch in height in the last 3 weeks since this was done. Very slow growth rate.

OK, I see why you think it's a nutrient uptake issue. purple leaves and all. Some pepper varieties are very slow growing for me no matter what I do until the are transplanted to there final home. Tomatoes never give me a problem.
Purple stems on pepper seedlings are normal, purpled cots are normal for some varieties, purpled true leaves are only an issue when the soil temperature is too low.

I inoculated all early only once with BiotaMax and then AZOS a week so later I think, no negative effects there. Also watered in some compost tea later on, a week before potting up.
I haven't used Actinovate in the mix until the full root dip at transplant, but I don't see why Actinovate would effect very young seedlings in any negative way unless there is some severe competition for nutrients. You said you used EM1 bacteria, that's the TeraGanix product?

Ray, yup I used the EM1 mix by Teraganix along with the actinovate. I think the two combined are just outcompeting the plants for nutrients. That's the only explanation I have. Never had seedlings just shut down growth this early on and adding the actinovate and EM1 is the only change I have made from previous years.

I normally inoculate plants later on at plant out (using a dip method similar to the one Ami has described on this board) and that has worked well for me, but like mentioned I started using the actin/EM1 way earlier on these plants that are struggling.

I agree, if the only difference was EM1 + Actinovate, then the simplest explanation is there is some interaction between the critters at least in the constraint of pot culture that we don't fully understand that is effecting plant growth.

I think I am going to hit them with a shot of inorganic fertilizer to see if I can wake them up. If that doesn't work then I'm probably out of luck.

It would be interesting to know the PH of the medium. EM-1 contains 4 species of Lactobacillus. They produce lactic acid. Could the introduction of Streptomyces Lydicus cause them to somehow create more acidic conditions than normal? if the PH was low enough, that would account for the stunting and purple leaves. What made me think of this is this [URL="http://infrc.or.jp/english/KNF_Data_Base_Web/PDF%20KNF%20Conf%20Data/C5-10-201.pdf"]experiment in Japan[/URL] and the problems with culturing Lactobacillus plantarum and Streptomyces Griseus together.
Inorganic fertilizer may have no effect if the PH of the soil is too low or may make it worse. If the PH is very low, then increasing the PH would correct the problems with the seedlings.

Good thought Ray. I did end up using an inorganic fertilizer on a few of the ones I could spare. If they die or just aren't saved, it won't be the end of the world.

I'll see if I can get the pH of the soil tested but at the moment don't have a means to do so. May as well get it though -- seems like a wise thing to have.

Just an update. You hit the nail on the head, Ray. pH of the soil in the stunted seedlings peat pots was 4.5. Then I added some ground eggshells that had been simmering in water to the soil mixture and the pH jumped up substantially. So I went ahead and poured some of the eggshell & water mixture onto a few of the seedlings to see what happens. If they make progress, I'll do the same with the others.

Lesson learned. More beneficial bacteria is not necessarily better. Don't mix actinovate and EM1 with young seedlings.

Admittedly I am taking a stab in the dark with how much eggshell (calcium carbonate, aka lime) I am adding to each seedling but I'd rather experiment and see what happens than just let them die off.

Wow! PH 4.5, that's amazing. Did you check the PH of the EM-1 only inoculated pots? I guess those Lactobacillus really don't like strong competitors in the confines of a pot culture. According to Natural Industries, Streptomyces Lydicus can survive a PH as low as 4.0, but are only active at PH 5.0-9.1. Those Lactobacillus basically put Streptomyces Lydicus to sleep. Now I wonder if your human intervention to drive the PH back up would bring Streptomyces Lydicus out of dormancy and cause the Lactobacillus to try to lower the PH below 5.0 again? You might be a player in a microbial tug-o-war.:?:

I didn't check the EM1 only pots since they are all in the ground and growing well, but it would definitely be interesting. If there is a microbial tug-of-war as you say, I am hoping the actinovate (s. lydicus) wins out! I won't be adding any more EM1 to any of the beds where I used actinovate (I've had good success with it) just in case.

This has me thinking...I just started indoor bokashi composting which uses EM1 as the inoculant. Since I apply actinovate to the roots and as a foliar spray, should I avoid using the diluted bokashi juice (the run-off that occurs during the fermentation period) as a foliar spray? Could these two microbes compete with one another on foliage even though that isn't in the soil?:?

Thanks for sticking with the thread RayR. I know there are many others use who beneficial microbes, mycos, etc. on this forum. All input is welcome!