Pesky algae, please help! How to Stop Nostoc?

[Charis]

Some time ago blobs of jelly-like stuff began to appear in my back yard, mostly in the doormat. At first I thought it was some kind of jelly fungus but it turned out to be a species of blue-green algae called Nostoc. In fact it's neither blue or green but various shades of muddy yellow-brown, changing to black when dry.

It was a curiosity at first and I left it alone; but now it's beginning to spread all over the garden. Scrubbing with bleach will probably remove what's in the yard but how do I get rid of it from the garden without killing the plants? At the moment all I can do is remove the blobs by hand, but even a tiny smear will spread, and it seems impossible to stop it getting on one's hands or boots and spreading it even further that way.

Hope someone has an answer.

Thanks

[Kisal]

You should be able to clean it off of areas like your doorstep with a pressure washer. I would just borrow or rent one, unless you have enough other uses to warrant buying one.

If you've identified it correctly, it's actually quite healthy for your garden soil, You might want to research it further, before bothering to try to eliminate it. We get algae blooms around my area once or twice a year. They don't last long. Red algae would be one to be concerned about, but not the blue-green types. JMO.

[rainbowgardener]

It is a harmless and rather interesting creature. But it requires sunlight, standing water or consistent moisture, and phosphates to live. If you are having it in your garden it suggests possible over-watering and over fertilizing. If you don't want the algae, work on increasing your drainage and/ or decreasing your watering so that the soil dries out well in between waterings and don't use synthetic fertilizers.

Here's a nice article about them:

https://www.dgsgardening.btinternet.co.uk/bluegreenalgae.htm

It says they are nitrogen fixers and may have been originally responsible for creating the oxygenated atmosphere that supports all the life on earth.

[Charis]

Thank you both,

I'm glad Nostoc is harmless (I posted a picture of it on the Natural History Museum forum - https://www.nhm.ac.uk/natureplus/index.jspa?fromGateway=true and one of the experts there identified it, so think that must be right.

The excessive rain this year must have a lot to do with its increase, but there's not much to be done about the British weather! My soil seems about average re drainage, just ordinary loamy garden soil. Not sure how to improve drainage unless maybe dig some sand in? But to do that for the whole garden would be a BIG job.

I haven't used much artificial fertilizer, except a good sprinkling on the raspberries and blackcurrents (although the Nostoc doesn't seem to have got to them yet).

I have noticed that earthworms seem to like it. In fact there seem to be a lot of very small worms, especially under the bigger blobs. A worm nursery with lots of nice soft baby food?

I'll just put it in the compost bin (right next to the rhubarb patch as rhubarb is supposed to be a very greedy plant) if it gets too invasive.

Thanks for the link, will look it up.

[Charis]

Yes, the top picture on the page you gave is exactly like the stuff in my garden.

...Although I don't accept the assumptions behind the idea that they "may have been originally responsible for creating the oxygenated atmosphere that supports all the life on earth".