Author Topic: Pond weed  (Read 1967 times)


  • Quarter Acre
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Pond weed
« on: May 22, 2017, 09:32:13 »
How do you get rid of pond weed, barley straw or chemicals or wind it on to a cane  :BangHead:
Spring has arrived I am so excited I have wet my PLANTS

Allotments 4 All

Pond weed
« on: May 22, 2017, 09:32:13 »


  • Hectare
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  • Vendée, France
Re: Pond weed
« Reply #1 on: May 22, 2017, 12:10:24 »
Lots of pond weeds.  Blanket weed can be wound up ona rake or fork and then left on the side for day to dry out and let critters escape.  Then bung it on teh compost heap.   Barley straw tied up in some old tights is supposed to help control it.

Duckweed can be scooped out with a old sieve.

Iris pseudacorus - wade in and pull up then dry out and chop up for composting before it "terraforms" your pond.

Definitely no chemicals if you want wildlife.  Be careful about using nitrogen fertilsers near the pond as that will leach into the water and encourage weed growth.  Cover a third of the pond surface with something like water lilies to reduce light levels in teh water and also provide shelter to beneficial critters.
Obxx - Vendée France


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Re: Pond weed
« Reply #2 on: May 22, 2017, 12:53:34 »
Duckweed is a pain when it gets in between the leaves of your marginal plants - you can use a wide flat spray on your hose to move it out, but if there's no un-planted corner to aim for, most of it will end up among other marginals - especially the ones you have just cleaned out...

I put in a lower (40cm) pond with a waterfall I could fix a sieve under - I only had room for 120 x 60cm, so it's easy to clean - though it breaks the normal rules about the largest pond being the lower one - but I only use it when I'm washing duckweed out of the main upper pond or when I want to sit near the waterfall.

The flow plus the flat spray are very, very efficient - it only takes me 20 minutes to clean out everything visible so it takes weeks to become a problem again.

Another solution I've used is to plant marginals in big pots inside the pond with their rims above the water. Good for controlling irises, sagittaria etc.

They look good: hard-glazed ones are best - they need wet strength - a pattern round the rim looks nice. I even grew a manageable but still impressive 100cm+ tall G.manicata this way.

With a microholding you always get too much or bugger-all. (I'm fed up calling it an allotment garden - it just encourages the tidy-police).

The simple/complex split is more & more important: Simple fertilisers Poor, complex ones Good. Simple (old) poisons predictable, others (new) the opposite.


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Re: Pond weed
« Reply #3 on: May 22, 2017, 17:08:38 »
I grow watercress in my ponds.It seems to help control the duck weed as it keeps the nitrogen levels lower.
Beautiful tiny white flowers so looks good.I just buy a bag of watercress salad from any supermarket,leave it in a bowl of water for a couple of weeks until the roots form and chuck it into the pond.Works for me anyway.