Experiencing panic stations with your water garden!

Emergency remedial action is to pump in oxygen by turning on a fountain or stream. If there is nothing like this incorporated in the pool, spray water from a hose at a height that allows the jet of water to push air under the surface. Tap water contains quite a bit of oxygen and although it is not the best thing for fish under stress, it is the least of evils and dropping it in or gushing it forcefully into the pool dissipates a large portion of the chlorine it contains.

If a complete pool clean in the near future is out of the question, carry out the emergency remedy of a partial water change of one third, refilling with water from a hose as above and treating with pool conditioner is a remedial option. For large pools, various retail products such as Aquaplankton have had some success in breaking up some of the pool detritus. Otherwise get to it as soon as possible. If you can do this in later September /early October, the water is still warm, and the wildlife and plant life has still a bit of growing time to recover, the water can age, nothing is hibernating and everything is out that wants to be out.

And here is what you'll need...

General:

  • A pump capable of pumping thick, muddy water and a large bore hose suitable for the pump and siphoning.

It may very often be necessary to supplement any pre-filter on the pump with the sieving effect of a large lily basket or such like, otherwise your are constantly clearing detritus from around the pump.

  • Also plan where it is going to go. A compost heap will only take a certain amount of very liquid material whilst small drains can easily be blocked by the thicker stuff. If you pump it straight onto a flowerbed or a shrub border, it just lies like a thick chocolate icing asphyxiating terrestrial plant life as effectively as it was suffocating the pool. Aim for a manhole drain cover and lift it, but dont leave it uncovered. People have a nasty habit of falling into holes that were previously safely covered over.

 

This large pond at Blagdon Water Gardens has a tranquillity that belies the problem beneath surface of the water

 

Three days hard work reveals its potential problems, only partially cleaned out and look at the tons of muck.

 

 

 The tubs are full of lily cuttings and a few fish.

  • You will need buckets for muck and containers for wildlife, fish and plants. I use old fibreglass pools with nets over them, but water butts would do just as well.

 

Old but sharp knives or old pruning saws are essential for dealing with well knotted and knitted together marginal plants. Note the plastic sheets and the pipe. This small pool only needed siphoning no pump constantly clogging up.

 

A plastic dustpan and brush is essential at the later stages; a very coarse brush for cleaning off the pool-sides is useful; a shovel; a good net, and some long waterproof gloves are in my mind essential having caught some nasty viral germs and bacterial upsets from cleaning out ponds.)

  • Water supply and hose for washing down, watering down (see below) and refilling.

If dividing the plants and replanting is on the itinerary:

  • A polythene ground sheet is useful surface for storing plants and splitting them on.

  • Two garden forks or a sharp spade, an old pruning saw and a garden knife. Scissors, secateurs and trowel may be useful.

  • All the necessary ingredients for replanting: fresh soil (good garden loam will do), probably new baskets, hessian liners for the baskets and topping gravel.

If you have fish in your pool and the cleanout may take a long time:

  • They will need to be kept in the cool with some aeration from an air pump.

  • Net for catching fish.

  • Tap water conditioner.

Method

Allow yourself plenty of time. It always takes longer than you expect and it is hard work, so get some help too.

Save as much of the clean water from the surface of the pond as possible that is if it isnt completely stagnant. Use this to store the fish in. It will also be useful for helping age the tap water you use to refill the pool. It will act like a yoghurt starter by introducing a thriving culture of the right bacteria into the pool.

Pump out the rest of the muddy water to a preordained place. You might want to water down some of the thicker mud with fresh water from a hose so that it can be sucked up through the pump.

Large heavy amounts of tangled roots and thick mud can be left on the side to drain and to allow the insects, animals and other strange organisms to make their way back into the pool at any time at their convenience. The population of frogs can seem enormous as you rescue one after another, until you realise quite often that it is the same one that keeps escaping from the quarantine you place it in.

 

Frogs can be stored in a deep sided bucket, but they will probably manage to get out.

 

 

 

 

Characters like this dragonfly larva will make their own way home unless of course you need to keep them out for a time, in which case pop them in a bucket of pond water.

Whilst the pond is emptying, you can remove the marginal plants and divide them if necessary. You may find it necessary to divide them in situ just so that you can get them out! When you are struggling with the hippo like proportions of some of the root masses, the old pruning saw comes into its own. However take great care if the pool has a flexible liner to not slip or accidentally cut too far.

 

 

The old pruning saw being used to cut up this mass of sweet galingale.

On this occasion the giant sausage of root ball had to be wrestled into the bottom of the pool in order to be able to cut up from underneath and between the planting baskets.

If there is no time for a replant, carve the plant material away from the original planting baskets. If you do this carefully this is often the best material for propagating new plants especially when it comes to the precious delights of irises and lilies. The alternative of dividing up the contents of the planting basket often means total destruction of the basket.