From

Location

Message

Date Posted

Grittyville, WA

This is a good stepping stone from Cornell University, a few page pdf article:

http://greenhouse.cornell.edu/crops/factsheets/nitrogen_form.pdf

I found it very helpful. Rethinking everything...

4/15/2019 3:45:06 AM

Bethlehem CT

Good article. I found the picture that demonstrates nitrogen toxicity on plants very interesting. I have seen that happen to plants in my garden many times. Usually, I will see it after a plant comes out of the greenhouse and is set outside. I have always thought the problem was the plants were not properly hardened off to outdoor conditions. Which is actually only half of the cause, I did not know that it was actually a type of Nitrogen toxicity taking place, which occurs when plants are taken from a warm environment and then moved to a cool one. Luckily I have found that type of damage to be short lived and the plants will recover very quickly once the temperatures warm up.

4/15/2019 8:03:13 AM

Bethlehem CT

Acidification and alkalinization of the soil by different forms of Nitrogen is far more crucial in plants that are grown in the greenhouse in pots of soilless media. Drastic pH swings occur over a relatively short period of time. Bedding plant growers have to be ready to react if they are growing a crop that has a long cycle and will need to be in the pots for several months before sale. Most growers want to get their plants sold and gone before they have to start to manage for pH. WIth some crops that may not be possible and you will start to see iron deficiciency as the pH becomes too high.(Toxicity if it gets too low) Luckily for us pumpkin growers we grow in "real" soil that acts as a huge buffer to the effects of the fertilizers we use. That being said certain types of soils have less buffering capacity than others and a wise grower needs to be aware of acidification or pH increase caused by the type of Nitrogen they are using. Thanks for posting the link Glenoma.

4/15/2019 8:13:29 AM

Lakewood, WA

This explains why Matt D. does not recommend the use of Miracle Grow fertilizer, since it can lead to ammonium toxicity.

I will need to re-read the article, maybe a few times, in order to understand it more completely.

Thank you for posting, I appreciate it. I guess I am on the right track for my patch, eventually :)

4/15/2019 2:13:01 PM

Grittyville, WA

I see ammonia as the number one concern/drawback with miracle grow. Miracle Grow may be correctly balanced for some uses but in a time of year/ situations where you might have excess ammonium it wont correct that excess. Ammonium can be
good for soil biology. Its going to suppress plant growth though. I read that it competes directly with potassium.

It gets confusing because, for example,
I am seeing a potassium deficiency in the leaves but I know the potassium levels are fine.

I think ideally soil cables go in about 2-3 weeks ahead of the plant to get the soil biology going, so that ammonium/urea fertilizers are then beneficial.

I am unsure which fertilizers would be beneficial prior to having normal temps & soil biology. Maybe starting with nitrate fertilizers and aiming for neutral ph.

4/16/2019 5:05:34 PM

Grittyville, WA

Talking about extreme conditions here. Ammonium will benefit plant growth under normal conditions.

Soil does buffer the ph change associated with excess ammonium more than peat moss. Even amended peat moss with carbonate added doesnt really buffer ammonia very well, I think because the microbiology is still missing. Compared to healthy soil there's not a lot of habitat for bacteria within a mostly acidic peat mix even if it does contain buffering material (carbonate). Well that sums it up!

4/16/2019 5:16:45 PM

Grittyville, WA

I have not had any other problems with miracle grow, the thing that matters is whether the nutrient profile of the fertilizer in question matches what you need. MG often has come close to what I need although I have found some others that are closer to what I need & less expensive.

4/16/2019 5:27:44 PM

Lakewood, WA

It sounds as though ammonia is another one of those line items where some is fine, but too much just too much! lol

4/16/2019 8:26:11 PM

Morgantown, WV

Some fertilizers are specifically acidic, especially soluble all inclusive ones. These fertilizers have not been developed for your natural garden soil, and will not give you optimum growth in natural soil. Jack's is a national brand, and one we use at the university, which our formula is specifically acidic to counteract the calcium carbonate in our municipal water source.

Miracle grow has been developed to be used with... guess what!? Miracle Grow Potting Mix. Big surprise, I know. Soilless mixes comprised of mainly peat and vermiculite, or even peat and perlite, are inert, and do not really contribute to nutrition other than holding and releasing nutrients in solution. When you start with nothing, you can advise a specific amount at a specific rate that satisfies quality plant growth.

When you change the ratios used, or add natural soil, many things other than the fertilizer become players in the game. Natural soil has different buffers, different irrigation, and far different biology than a pot-grown plant.

The Nitification Cycle of natural soil is one of the most complex aspects of soil fertility and cannot be boiled down to "ammonia is bad". Ammoniacal Nitrogen is available, and leaches out well, which is why miracle grow uses it for weekly feeding regimens. Misuse, or change of media, affects its performance.

Short and sweet, MG is for pretend gardeners who don't know what to do. If you're ok with that, use it. If you want to exceed your own expectations, learn how your nutrients work in your natural soil, and mitigate influxes as well as deficiencies.

4/16/2019 9:19:07 PM

Grittyville, WA

Pretend gardeners.. Less call them "less serious". ...Includes me on most days.

I am sure miracle grow potting mix plus their fertilizer is a good combo for certain plants with certain water. The water... Is a good point. We have very littlr calcium in our water. I doubt they formulate ours differently so we end up getting hit harder by the ammonia.

4/17/2019 2:42:48 AM

Grittyville, WA

So far this year has been a struggle for me. There's always next year... Can't win 'em all but I do think of new ideas when discussing problems so there is hope. I will post my latest idea in a few days.

4/17/2019 2:49:45 AM

Morgantown, WV

Sorry, pretend gardeners is probably not the best term... let's say beginners instead :)

4/17/2019 7:43:06 AM