Seaweed, sulfur, and acidic soil

11 years ago

I understand that seaweed is a great addition to compost, or to garden soil.

I have access to copious amounts of seaweed, but it's a variety that's known for its particularly high sulfur content (you can smell it from quite a distance on the beach, and I can track down the species name if anyone thinks it would be helpful).

I also live in an area that has acidic soil.

As I understand it, sulfur is commonly used to lower the pH for people who have alkaline soils. Lowering the pH is certainly not what I want to be doing.

So...should I give up on the idea of trying to incorporate this particular seaweed into my compost or garden beds? Should I use but try to balance it out with lime? Am I worrying unnecessarily?

Thanks!

Featured Answer

toxcrusadr

11 years ago

It's a good question that I don't have a definitive answer to. But I can say that the sulfur in the algae is most likely from sulfur compounds rather than elemental sulfur (which is what is used to lower pH). So it is not automatic that it will have the same effect. If composted first, the composting process *should* drive all organic matter towards neutral pH. I'll confine my answer to that and see if anyone else chimes in.

Comments (12)

pnbrown
11 years ago
I have never heard of any seaweed acidifying soil.
Related Professionals
Quincy Landscape Architects & Landscape Designers · Bowie Landscape Contractors · Bridgeview Landscape Contractors · Brunswick Landscape Contractors · Cordele Landscape Contractors · East Haven Landscape Contractors · Hoover Landscape Contractors · Melrose Park Landscape Contractors · Pleasant Prairie Landscape Contractors · Thonotosassa Landscape Contractors · Kingsburg Landscape Contractors · Crestline Decks, Patios & Outdoor Enclosures · Dearborn Decks, Patios & Outdoor Enclosures · Grain Valley Decks, Patios & Outdoor Enclosures · Monroe Decks, Patios & Outdoor Enclosures
josko021
11 years ago
What seaweed is it? I use rockweed and eelgrass with excellent results.
leira
Original Author
11 years ago
The seaweed (really an alga, apparently) is Pilayella littoralis.

There's apparently a journal article titled "Isolation of humic acid from the brown alga Pilayella littoralis" which I'd love to read, but I don't really care to spend $35 for the privilege.
bluegoat_gw
11 years ago
I doubt very much if the little bit of sulfur in the algea will change the pH of the soil. The addition of calcium carbonate will easily neutralize any possible pH change and also add an important nutrient to the soil. If you use the algae in your compost, avoid adding CaCO3 to the compost since it causes a loss of nitrogen.
Kimmsr
11 years ago
It always amazes me when people spend that much time and energy trying to find ways to dispose of "waste" materials without thinking that maybe this could be used in gardens. After some 40 years your DCR should have some idea of what affect this algae would have on soil and whether the sulfur compounds might affect soil pH.
Since things such as tree leaves and pine needles do not lower soil pH I would doubt that this algae would either.
toxcrusadr
11 years ago
What's a DCR?
leira
Original Author
11 years ago
toxcrusadr, the DCR is the Massachusetts Department of Conservation and Recreation -- the oldest regional park system in the United States. They oversee quite a bit of public land.

Here is a link that might be useful: DCR
josko021
11 years ago
I got a hold of some of that seaweed (I think we call it 'Mung' down on the Cape), and I would be eager to add all I can to my garden soil. Maybe let it sit in a pile for a while to leach salt out first, or add it in as a compost green. I expect it would mix very well with leaves or similar browns.
mackel_in_dfw
11 years ago
Seaweed in small doses for micronutrients-good- seaweed as a carbon source-???. Kelp, for example, in generous servings, contains excessive salts, growth hormones, and anti-mychorrhizal properties. That's my final answer, Chuck. We use kelp extract anually, but the amount of seaweed contained in the yearly application is *tiny*.

Mackel
blazeaglory
11 years ago
Didnt growers of old in Ireland used to grow their potatoes straight in seaweed on the land?
mackel_in_dfw
11 years ago
They all came over here cuz they monocultured potato, arrived and disovered tomato, and the yankees amongst 'em call it "pototto". Little known to the English, the Russians came up with the secret to potato ("Vodka"), then some of the Irish intermarried, and now we have the bloody mary...

Mackel