When / how to rejuvenate soil in raised planters?

[MossRoad]

If you're going to grow things in raised beds, and every year you add soil amendments for fertilization/aeration/moisture control, etc., which is good, eventually you're going to exceed the height of the beds. So then you have few choices.
- Make the sides higher.
- Remove some of the soil to allow for more amendments.
- Give up amending, create a growing medium, and use fertilizers in place of amendments.

That's about all you can do.

 

[ultrarunner]

Composting and other organics are great for gardens in native soil. Potting mixes are made to drain quickly to avoid saturation and root rot. That’s why greenhouse growers use liquid fertilizers. Composts and other such things will slow drainage and keep the roots too saturated in a container situation. Growing in pots is not the same as a garden.

Guess it is a good thing it's just flower boxes... one sleeve of miracle grow last better part of a year...

One friend does hydroponic vegetables... no soil at all in a green house... he pulled out a carrot and it looked perfect and the pushed it back in so it could grow some more.

I come from a long line of composters and organic Dairy farmers...

When living in the city the composting created a perfect habitat for rodents...

 

[CalG]

If you're going to grow things in raised beds, and every year you add soil amendments for fertilization/aeration/moisture control, etc., which is good, eventually you're going to exceed the height of the beds. So then you have few choices.
- Make the sides higher.
- Remove some of the soil to allow for more amendments.
- Give up amending, create a growing medium, and use fertilizers in place of amendments.

That's about all you can do.

Remove some of the soil, set it aside, Replenish the volume in the raised beds from the finished compost pile, then put the removed soil back into the compost pile. Viola!

SOIL is one of the most important ingredients to add to compost. It's got lots of the "good stuff" in it. Sort of like yogurt starter ;-)

 

[MossRoad]

Remove some of the soil, set it aside, Replenish the volume in the raised beds from the finished compost pile, then put the removed soil back into the compost pile. Viola!

SOIL is one of the most important ingredients to add to compost. It's got lots of the "good stuff" in it. Sort of like yogurt starter ;-)

Yep. However, you're always going to end up with more soil than you can use. That means spreading it around, more planters, or in my case, a berm that's now 3' high by 8' deep by 135' long! 26 years of composting leaves, making flower beds, garden waste, tree branches, etc. ads up.

 

[CalG]

I've got four "tractor size" piles of organic material in various stages of soil making. For years, the maple leaves were just dumped over the bank. Lots still are even this year, I just can't use them all.

But.....

We run our garden in "beds" that are on the ground. Elevated as much as a 2X 6 will take to level off. Walkways between. I call it "Figure Eleven" gardening. The pathways are used as grass and leaf mower clipping dumps. Leveled for walking. Great places for the vines to run (Squash and cukes)

What I find is that more "soil" is needed every year to keep the level of the beds up to the top of the boards. The organic material mineralizes. and in doing so condenses.
When the beds are worked in spring, it appears that the soil level is high, but a few rains in, and it all slumps down. That's when the FEL is handy to bring out some "top dressing. .

I guess that's how it works here, can't say for how it works for you. Plus. There are always low spots in the yard that need leveling out ;-)

 

[Larry Caldwell]

If you want to kill everything in the soil and then depend on this stuff forever. I once bought some Miracle Grow soil. Great first year. Then didn't buy anything to put in the soil. NOTHING would grow until rejuvenated about 4 years later.

I think your problem was avoiding native soil. Dirt is a living thing, with microorganisms that have lived there for a thousand years. Treat them with respect and the plants will love it. Your MG soil was a foreign thing. Did it even have earthworms in it?

 

[Larry Caldwell]

Understand that there is no chemical difference between nitrogen, phosphorus, potassium, or any other compound between a commercial fertilizer and chemicals that occur in organic matter. A simple chemistry class will explain this. Organic matter is great for field gardens because it provides tilth and water holding capacity to soils, neither of which are a issue with container soils.

Anything can ruin the fertility of soil if it is wrongly applied. Fertilizers, particularly nitrogen, can burn plant roots badly. OTOH, that same nitrogen is necessary for microorganisms to break down cellulose and lignin to form new soil.

One soil amendment nobody seems to mention is charcoal. If you find a source for raw lump charcoal without the BBQ additives, break it up into small stuff and mix it into the soil. It will absorb nutrients and release them slowly over years. Lump charcoal has big pieces, and the best way I have found to break it up is put it in a feed sack and drive back and forth over it a few times.

 

[jyoutz]

I think your problem was avoiding native soil. Dirt is a living thing, with microorganisms that have lived there for a thousand years. Treat them with respect and the plants will love it. Your MG soil was a foreign thing. Did it even have earthworms in it?

Native soil is great - in the field. Not so much for containers. Too heavy and poor drainage.

 

[mapper]

Anything can ruin the fertility of soil if it is wrongly applied. Fertilizers, particularly nitrogen, can burn plant roots badly. OTOH, that same nitrogen is necessary for microorganisms to break down cellulose and lignin to form new soil.

One soil amendment nobody seems to mention is charcoal. If you find a source for raw lump charcoal without the BBQ additives, break it up into small stuff and mix it into the soil. It will absorb nutrients and release them slowly over years. Lump charcoal has big pieces, and the best way I have found to break it up is put it in a feed sack and drive back and forth over it a few times.

Recall reading a few years back that some archeologists discovered some ancient garden areas in the Amazon that had been created by the indigenous people there. The soil was amended with pottery shards and charcoal. The garden areas had been abandoned for a long time but still were way more fertile than the adjacent area.
The Amazon rain forest is notorious for thin poor soil that will lose its fertility very soon after the forest is cut down. This has led to a lot of devastation of the rain forest due to "slash and burn agriculture"

 

[the old grind]

I gather charcoal with ash and dirt from around the 'fire pile' in my avatar 1-2x/yr and stir it into the compost. Charred limb lumps are screened out when 'harvesting' and get stirred back into the pile. (seen in the pic beyond the 'shuttle-craft')

Nice to have a Weed Gator (TM) to gather (vs just cut loose) wet green mat'l to shore that can be layered between pine straw & twigs or leaves.

Because my soil is mostly sand (a former pit) compost is best for leveling lawn spots, esp for volume with only ornamentals vs a garden per se. The only 'dark' soil I have is along shoreline and it's a bit of work to get roots & weeds out of it to add. (willow, horsetail, etc.)