Propagating Water Garden Plants
Propagating Water Garden Plants
A large number of pond plants can be propagated without any significant problems. In most cases, the simplest method is to divide the rhizome or rootstock. If a plant does not thrive, however, or if dividing it involves too much work, you may be able to propagate the plant from seed, depending on whether it is suitable for this method. Some plants also form long shoots from which daughter plants develop.
For propagating purposes, cut off the underwater shoot with a sharp knife or secateurs, but only cut off shoots that have already formed their own roots.
Division of rhizomes
In the autumn or spring, remove the plant – a water-lily for example -from the pond so that a rhizome can be divided. During this procedure be careful that the rhizome is not damaged and try to obtain as many roots as possible. You will only be able to divide the plant if the rhizome has formed lateral branching rhizomes (daughter plants) with their own roots.
Cut off the daughter rhizome with a sharp knife, ensuring that the cut surface is as small as possible and no stump is left on the mother plant, which might begin to decay. The wound surfaces should be dusted with charcoal powder to prevent infestation with decay-promoting bacteria.
Very robust plants with branching rhizomes (reeds, for example) cannot be taken completely out of the pond. In such cases, expose only one end of a rhizome and cut it off with scissors in such a way that it has as many roots as possible.
Cover up the cut end with matter from the pond floor. The newly acquired young plant can now be planted in the desired position.
Dividing the rootstock
Pond plants with a well-developed rootstock (e.g. species of marsh grasses and marsh marigold) can be propagated from the division of the rootstock. Take the plant out of the pond in the autumn or spring and use a long, sharp knife to cut the rootstock into two, equal-sized parts. In the case of marsh grasses, the rootstock is often so well developed that it is recommended simply to chop it in half with a spade. The nutrient supply to above-ground parts of the plant will be somewhat limited by this damage to the root.
Propagating from seed
Propagating from seed is time-consuming but with some plants the effort is well worthwhile. Use this manner of propagation only with plants whose seeds are easy, to harvest, that are problem-free in respect of germination and which grow easily, like somespecies. You can only work with pure species, not with hybrids.
Propagating from Iris seeds
It is worthof Iris sibirica and Iris pseudacorus as, with correct care, they will produce very many, easily isolated, individual plantlets. Like many other northern European marginal plants, the Iris is a cold-germinator and requires low temperatures for proper germination.
Do not remove the seed capsules until they are dry and brown. Simply break open the capsules with your fingers and shake out the seeds on to a piece of paper. They should be kept in a cool, dry place.
Preparing and sowing the seed
Around the middle of the second month of winter, the seed should be prepared for sowing out. Sprinkle them in a shallow dish which has been lined with damp blotting paper or kitchen towel and then stand the dish in a refrigerator. Keep the blotting paper or kitchen towel slightly moist. After about two weeks you can take the dish out of the refrigerator and remove the seeds and paper. Pack loosein the dish. Distribute the seeds on the compost and cover them with a very thin layer of compost. Moisten the compost well without making it waterlogged. Stand the dish on a windowsill at room temperature and make sure that the compost is kept damp. After about two weeks, the first small Iris plants will appear, looking rather like grass at first glance.
When this miniature “lawn” has grown to about 5 cm (2 in) tall, you should prick the plantlets out into individual pots. Turn the dish upside down and carefully lift out the tangled mat of roots. Carefully separate the mat with your fingers, trying to damage the roots as little as possible. Gently pick the plantlets apart and plant every three or four of them in pots containing loose, nutrient-rich. The plantlets should be placed in a sunny window for optimal growth. Make sure the compost is never allowed to dry out. When the plants are about 20 cm (8 in) high, they can be planted out in the marginal zone from about the second month of spring onwards.