the middle ground for this is to put the compost down on top of the ground and cover it with a mulch....

Wow, ok, that explains the troubles I've been having. I've had a hell of a time with germination. Transplants do ok, but seeds don't want to sprout in my beds.

Time to lay off adding compost.

References please?

Your little pearl of wisdom has been one of the most helpful things I've read on these boards. Thank you.

That web site, claiming to be the best compost information on the web, says that the seeds don't germinate because of a lack of Nitrogen in the soil. Sorry, but seeds don't need anything to sprout except water. Seeds will sprout in a wet paper towel. No Nitrogen there.

I think that newly sprouted seeds are vulnerable to attack from the same bacteria that is living in the compost. Especially if you are planting in warm soil; levels of bacterial activity are closely related to temperature.

In nature the seeds are in the soil/litter for the entire winter and get a chance to germinate before the soil warms up enough to encourage bacterial growth in the litter. It's us gardeners who are trying to germinate seedlings well after the soil has warmed up.

But the bottom line is; don't plant in compost unless it's dead compost. Everybody extolls the virtues of live compost; how the bacterial community deters pathogens and pests, and how the plant lives in symbiosis with the microfauna. But nobody seems to make the connection between compost bacteria and seedling mortality.

What I think I'll do in the future is try to find some soil underneath the surface of the garden bed that has no visible compost, bring that to the surface, and plant seeds in that. Once the seedling has sprouted, its roots will grow out of that non-compost soil, into the compost soil and make the adjustment to life in the organic garden.

Seems like someone would have noticed the problem with seedling mortality and come up with seeds that tolerate live compost. Oh well. (And, so much for all the self-anointed 'experts' and their theories about compost and seed germination.)

My bile comes from seeing (and getting caught up in) the many fads that seem to sweep through the gardening enthusiast community. Seems as if I have too much compost in my garden beds. I'd never even heard that it could happen, but I've managed to do it.

I have been dumbfounded by the lack of germination of certain vegetable seeds in my beds. I thought that I had done everything, and done it well. Apparently, I have done things a little to well. Only transplants and the hardiest of vegetables are doing well in my garden beds.

I had planted some carrot seeds back in April. Well, they have sprouted this week. That's only 10 weeks to sprout a few carrots from the many seeds I'd planted. And the peas, which virtually grow themselves if you give them a chance? They are off to a very slow start. Sheesh.

I'm still learning.

This is one of the reasons I allow my compost to cure for an extended length of time.

Lloyd

Sandy

Lloyd

The reason I do this is because it helps me keep all kinds of organic matter, from yard waste to kitchen waste to cardboard and paper, moving through stages in the various areas I have to contain or corral it, and keeps it moving into the garden areas AND cuts down on the need for another type of mulch. I use closed garbage cans for kitchen waste composting, and in the summer with lots of green stuff growing they fill up faster than they break down, so as soon as it's not critter-attractive, I need to dump it and let it finish off, either in my open pile area or in the garden somewhere. I often don't want to mix newer compost with older, so I will look for a way to go ahead and utilize it in the garden; or, if I am collecting a material is already essentially like a fine mulch, it's less hassle to just place it directly into the garden than put it in a bin or pile and fork it out later.

Plus, it spreads out my composting chores into more freqent, shorter efforts rather than marathon digging and spreading events, which works better for me as form of ongoing exercise. plus gets me out in the garden to inspect and enjoy different areas more frequently.

compost loses nutrients when left exposed? ... where do they go?

compost inhibits seed germination? ...tell that to all the plants that grow in my compost pile...

there is a difference between live and dead compost? I don't even know how to respond to that one....its the microflora and microfauna that make compost a great soil amendment... whether its finished or not...

Soil can only do one thing at a time? Like its a left handed pitcher with sore thumb..

Much of what is happening in your soil and your compost is simply biology and chemistry... its not magic...

Just great! Two classes I slept through!

Lloyd

You say that compost does not inhibit seed germination? Do a google search on the terms "phytotoxic compost" and read the book titled "Compost utilization in horticultural cropping systems" by Peter J. Stoffella, Brian A. Kahn. You'll only get random pages, but it's more than enough to convince a person that, yes, indeed, unfinished compost does inhibit seed germination.

Here are the names of some of the phytotoxic compounds in unfinished compost; acetic acid, butyric acid, proprionic acid, valeric acid. Professional compost scientists say that finished compost is compost where bacterial activity has dropped to a low level and that's the safe compost.

In fact, they talk about raw compost, high in C content, as an effective weed suppressant because of its phytotoxic properties.

It's all the woofing and barking about nitrogen deficiency that's hooey.

That book costs nearly $200 new, but I might spring for a used one for $68.

"Observations of crops (including legumes) planted on soil to which leaves have been applied indicate that plants suffer from a temporary N deficiency unless additional N fertilizer is added."

I've seen N deficiency in wheat due to leaf application so I tend to believe it can happen.

Lloyd

But the reason the field with the leaf-only compost was not green was not because the soil lacked Nitrogen, it was because the leaf compost was not finished composting because the compost lacked Nitrogen. While it was finishing composting after you spread it on the ground, the soil had the phytotoxic acids in it. I'll bet that if you spread that same leaf compost in the fall, you'll get a better outcome.

But the issue of seed germination is orthogonal to subsequent plant growth. Available Nitrogen for plant growth was never the issue when seeds failed to germinate in my garden beds loaded with compost. Seeds don't need fertilizer, they only need water.

It was the fact that the compost was still active that foiled seed germination. The ongoing bacterial activity was producing the phytotoxins. Your field with the purely leaf compost was in the same state; unfinished compost. Only when the leaves finished decomposing did that wheat really start to grow.

I suppose I could have added some N fertilizer but I wasn't willing to go to that expense for a few acres of wheat.

And it wasn't that the seeds didn't germinate, there was excellent germination in all areas of the field.

And trust me, if compost goes out of my yard, it's mature.

But we digress from the OP. It's possible there can be some issues with immature compost with some plants on some soils. Kinda wishy washy.

Lloyd

There were several lessons that I learned today. One is that unfinished compost is hard on root growth and will actually prevent germination. It's caused by the phytotoxic acids that are an intermediate compound in the compost process. Lack of Nitrogen will slow the compost process as will lack of Oxygen.

Second is that soil pH plays a big role in soil fertility. pH above 7.5 will inhibit Ammonium and Nitric Acid absorption.

Third is that the end product of composting, humic and fulvic acids, are mediums for availability of the various elements needed by plants. They bind to the Mg, Mn, Cu, Fe, Ca and other elements, as well as Ammonium and Nitrous/Nitric acid, and make them available for the plant.

For me, today was a good day, and this was a very productive topic. I learned a lot. Thanks to Lloyd, jbann, and fanfortony for their contributions.

beet, chard, and several daisy-type flowers will be affected some, Black Eye Susan dramatically so (very small seeds). Radish, brassica, parsley and carrots will be affected. Bok choi is probably somewhat affected. Generally, the smaller the seed the bigger the germination difference in regular soil cmp to compost. Hope this helps.

I'm going to see if I can find a copy of that book in any of the nearby libraries. It is a bit technical for my knowledge level but it seems to be a great book and I will try buying it if I can't find a copy anywhere.

Thanks for linking that.

Lloyd

As to the seeds themselves, as mentioned above a lot depends on the type of seed, soil temperature, and the age of the seeds. Many times older seeds take longer to germinate and have a less successful germination rate.

It's my understanding that carrot seeds can normally take 2-3 weeks to germinate; longer if the soil is too cold and/or the seeds are old. This is based on info I've read, not on personal experience.

Last fall I started a new compost area that was to be turned into a vegetable patch this spring. Having started it late in the autumn, there were only a few inches of organic material applied to the ground and it never got hot enough to fully finish. I turned it once or twice in April as the ground started thawing, and the grass clippings had very little deterioration; they were mostly intact and kind of mucky like grass clippings get when you pile them up. No additional material had been added to the area since last December.

But that didn't stop the volunteers of cucumbers, lettuce, and, lastly, tomatoes from germinating -- thanks to those leftover, unpicked fruits that were thrown in from the garden last October. [I'm used to tomato volunteers, but the cukes and lettuce were surprises.]

I can't really speak to experience with carrots (maybe I'll grow some next year), but there could be a number of factors that influenced low and slow germination.

All the best.

I've never used straight compost in which to plant seeds but have had lots of volunteers in the cold piles.

Since using wood shavings as the brown in making hot compost I'm using it as mulch sometimes before it's finished. I fill a wheelbarrow with this stuff and wet it with alfalfa tea before using. Makes a very nice mulch. Not something I'd try to sprout seeds in but the mature plants are doing very well with it and it smothers weeds or makes them easier to pull.

One idea I like for veggie gardens is to pile the compost in between the rows and cover with straw as a walkway. Next season plant in that area and do the same with the new walkway which last season was the planting row. Gradually will improve the soil over the entire garden.

I think feeding the worms is a good way to improve the soil. All those tons of worm castings are the best fertilizer.

Thanks to all who posted good links - lots of great info.

I am seeing weeds starting to sprout in my garden beds along with the carrot seeds I had planted back in April. I'm guessing that the unfinished compost that was on that bed has finished composting and now seeds are able to sprout.

There's another lesson; to suppress weeds, use unfinished compost between the plants in your garden.

No doubt I would rather use fully composted material, but to say that the plants in my veggi garden will somehow be deprived of existing nutirents because the soil has to first deal with the uncomposted matter is absolutely absurd. I mean people please think about what you are saying before you say it.

What they mean is that if you take a high carbon material and incorporate it into the soil there will be a high liklihood of some nitrogen immobilization within that soil thus perhaps hindering quality plant growth. Thus soil has difficulty processing the carbon material and growing the healthiest plant. I've got pictures if you like.

Lots of credible sources of this information online if one can stop laughing so hard and look for it. If you can't find any, I suppose I could dig some up for you but it might have to wait until winter when I have some time to waste.

Sorry for being so absurd, I didn't have time to think about what I was saying. LOL

Lloyd

Where can I get your address? The book came and I'm going to read as much of it as I can in the next few days. I'll be hosting a family reunion starting on the 19th through the 28th, so I'll shoot it your way for that spell.

Edit: Ok. I sent you an email.

Paul