Blanket weed

[Kipper at sea]

Is there a 100% cure for blankit weed in a garden pond

[Martin Brown]

Don't introduce it in the first place.

[Huge]

Experience teaches me that allowing the pond to dry out is quite effective. :o(

[F]

We use Nishikoi Clear Waters.

[Brian Gaff]

Keep the water in motion and airiated if you can seemed to work in the old days, except for maybe one stagnant area under a tree where, no doubt debris got in and acted as food for the weed. Brian

[harry]

[AnthonyL]

I'm a novice to garden ponds and my friendly neighbour expert gave me a jar of tadpoles and a variety of plants. He didn't tell me there was duckweed and blanket weed in the mix too.

[F]

Our 'included in the price' duckweed came courtesy of the local garden centre despite me checking carefully that there was none in their containers. Obviously, there was some lurking in there. I'm still netting it out as it appears two years later.

Our frogs took up residence without being invited and deposit huge amounts of frog spawn each year that I end up taking to a pond in a park a mile or so away. Hopefully, the new generation won't be able to make the trip home to their place of birth.

[Chris Hogg]

Blanket weed is an alga, and like all algae is a primitive plant. The pea soup effect that occurs in many ponds in Spring is also an alga. Plants, including algae, flourish where there is plenty of nitrogen available to promote growth. In a pond, the nitrogen can come from fish food if you have fish and you feed them generously (more precisely, it comes from fish crap), or it can come from soil that you've used for potting up your water plants, if you've used ordinary garden soil and not special aquatic compost which borders on subsoil in it's nutrient content. Another source can simply be run-off from surrounding flowerbeds etc, in wet weather.

You can get algicides to kill the stuff off*, but I never use them. I'm not sure how harmless they are or whether they can damage wild-life in the pond and even goldfish (actually, the most damaging thing to wildlife in a pond _are_ the goldfish!). The best way I've found of keeping it at bay is never to feed the goldfish (they will survive, but in fewer numbers and rather smaller, and it encourages them to eat the duckweed), and only use aquatic compost for pond plants. I get very little blanket weed, but I do still get a little, and never get pea soup in Spring.

See

and

[Tim Lamb]

In message , Chris Hogg writes

I don't think it grows well in shade.

Sadly our pond forms part of the yard drainage system so gets lots of nutrients in very wet weather. I use the lawn rake to harvest the stuff (left on the pond surround so livestock can crawl back) and then compost it.

>

[www.GymRatZ.co.uk]

Yes. Cloverleaf Blanket Answer. You really need to know the volume of your pond then mix it up and watch your pond turn into a pool of milk for a number of days.

I find it best to remove as much weed as possible before dosing but once dosed it keeps the stuff at bay for the rest of the year.

[Brian Reay]

I filled in the pond.

Seriously, before that, every now an then (may be 2 years), I drained the pond, cleared the weed and gunge, and refilled. The pond was 12'x6' and may be 2' deep at the deepest point. I put the fish in a paddling pool. It was such a chore, I gave the fish away and filled in the pond.