Snowflowers add nutrients to the soil . . . how exactly?

[l008com]

i've been told this before, that sunflowers are good for the soil, that they add nutrients to the soil.

But i'm curious, how exactly do they do this? Do their roots magically give off nutrients as they're soaking up water?

Or is it more like, sunflowers die every year and their decomposing roots simple turn into nutrients.

Or is there some other method entirely that they are using to make the soil better?

 

[Meadowlark]

They are super good for the soil. They have a rather unique ability to "nutrient cycle".

As described in "gardenerbible", they absorb significant amounts of nutrients, especially N, P, and K. A deep root system enables them to absorb nutrients that other plants cannot reach. In addition to the primary nutrients, sunflowers also absorb and store micronutrients like copper, zinc, and boron. When they mature and decompose, they return these nutrients to the soil enriching it for the future.

Another important characteristic they have is the unique ability to perform phytoremediation. That is a process of detoxifying the soil by absorbing heavy metals and contaminates such as lead and arsenic. As the plants grow, they absorb these harmful heavy metals, and they are removed from the soil as the plants decompose.

A truly fantastic plant. However, in using them you should be aware that they also are allelopathic releasing natural chemicals that can inhibit other plants growth.

I use them to border my veggie garden where this allelopathic power comes in handy to minimize grasses like Bermuda spreading into the garden. They also make a great insect trap for the dreaded stink bug.

I've got photos somewhere that demonstrate the allelopathic characteristic and the utility as an insect trap....and can add them later.

Yes, I sing the praises of sunflowers in the home gardens.

 

[Meadowlark]

I've got photos somewhere that demonstrate the allelopathic characteristic and the utility as an insect trap....and can add them later.

Yes, I sing the praises of sunflowers in the home gardens.

Here's a photo of decomposing sunflower stalks on the border of my veggie garden...pretty clear demonstration of allelopathic... Alfalfa cover crop on the left inhibited and Bermuda grass on the right inhibited.

 

[l008com]

Another important characteristic they have is the unique ability to perform phytoremediation. That is a process of detoxifying the soil by absorbing heavy metals and contaminates such as lead and arsenic. As the plants grow, they absorb these harmful heavy metals, and they are removed from the soil as the plants decompose.

How does that work? If a sunflower absorbs heavy metals, then decomposes in your yard, isn't it just returning those heavy metals back to the oil?

 

[Meadowlark]

How does that work? If a sunflower absorbs heavy metals, then decomposes in your yard, isn't it just returning those heavy metals back to the oil?

Yes, phytoremediation requires that the plant materials be removed in order to be successful.

 

[Esther Knapicius]

Snowflower?

 

[l008com]

Yes, phytoremediation requires that the plant materials be removed in order to be successful.

Oh well no luck there. I of course don't dig up the roots. But I also just pulled all the leaves off my dying plants in the fall and just mulched them up next time I mowed. The stalks didn't go back into my lawn... actually one did. The other 5 are in my shed and ill probably eventually just burn them at "firewood". Hopefully my soil is fairly healthy.