After planting it is quite normal for a pond to turn pea-soup green. This is a natural process that the pond will go through. Once the plants begin to grow and establish themselves, the correct balance will be found and the pool should clear. Do not be tempted to empty the pool and refill as the whole process will repeat itself.
All our oxygenating plants are supplied in leaded bunches (see photos in Oxygenator section of Plants). Planting guide = 5 bunches per square metre. Fill a container to within half an inch of the top with garden soil and firm well. Gently lay the bunches horizontally around the edge of the container with the leaded end towards the centre resting on the soil, then cover the surface with washed shingle and firm down.
Some plants are either poisonous or cause an allergic reaction when touched. For the sake of safety, it should be always assumed that any plant could be a potential hazard if eaten or cause a reaction if touched. It is the responsiblilty of the purchaser to be aware of this.
This is a subject currently being mentioned in the gardening press and various gardening societies. It's very difficult to say when a plant can become 'invasive'. A plant supplied to northern England or Scotland might never be a problem, though might be in the West Country. Much of it depends on climate, soil, position, water quality etc. Often they find their way into streams, waterways, lakes etc, by people 'dumping' surplus plants.
They then take over and become a nuiscance, out-growing our native plants. Also, birds, especially ducks, will carry parts of plants and seeds from pond to pond, for example, duckweed. The worst invasive plant is 'Crassula Recurva' often sold as an oxygenator. I still see it for sale in garden centres. Don't touch it with a barge pole! It can swamp your pond and has become a severe nuiscance in various waterways around the country. There are a few others that have been thought of as invasive. Amongst these are Myriophyllum Aquaticum and Azolla. In your own pond they can be easily kept under control. We are monitoring so called 'invasive' plants and may withdraw them from sale at short notice if necessary. When choosing plants for a lake, bear in mind the growth rate.
By far the best method of planting aquatics is in the plastic containers especially designed for the purpose. We supply these in four different sizes. They are lightweight, imperishable and help to make the task of cleaning out the pond a much easier one. The containers should be filled with good garden soil or proprietary aquatic soil available at most garden centres. Also aquatic plant fertilisers in the form of sachets can be added one per basket
Before planting, water lilies should have all the old leaves and anchor roots cut back, then plant firmly with the crown just above the soil level. (Mail Order plants are dispatched prepared). When the lily has a long tuberous root, plant horizontally with the new shoots just clear of the soil. Finish off by placing half an inch of washed shingle over the top, being careful not to cover the new shoots. The plant is now ready for placing in the pond, however to encourage growth raise the container within six inches of the surface and gradually lower to the required depth as new growth progresses.
Marginals & Deep Marginals
There is no special method of planting this category of aquatics. However in general they should be planted in containers as you would a normal plant, following the recommended depth of water over the top of container as said on the supplied label. For example: Caltha Palustris 0-10cm. This means 0cm is water flush with soil and 10cm is depth of water over soil. Finish off with a topping of washed shingle.
Just pop them on the water surface! Stratiotes will often sink or turn on their sides. Don't worry, they should correct themselves in time. (You could give them a helping hand though!) Stratiotes will also sink in the winter and rise in the spring. Eichornia, Pistia, Salvinia and Trapa's are basically annuals. They are difficult to over winter. However, if you wish to have a go, place them in a container of half soil, half water and keep them on a window sill or in a heated greenhouse or conservatory. Good luck!
Hydrocharis dies right back in the autumn but seeds itself for the following Spring. Azolla and Duckweeds should be kept under control, as they can become rampant.