Potting New Lily Tubers
Remove any damaged or dead leaves and any soft or rotten portions of the tuber. Sections of the tuber with no active growth can be trimmed back. Trim off the white anchoring roots and open leaves.
For potting material, you can use pea gravel, aquatic potting soil or heavy garden soil (like moles bring to the surface when burrowing). Use no-hole Lerio pots or mesh baskets. When using fine soil in mesh baskets you will need to line them with burlap. Do not use amended soil or potting soils as they will float. We use rinsed pea gravel as it allows more air space and is less likely to dirty the pond water.
If you are using granular Pond Pearls transplanting fertilizer, blend it into your media before potting. Fill the pot three-quarters full of dampened potting material. Place the cut edge of the tuber against the side wall of the container. Tilt the rootstock at a 45 degree angle so that the growing tip is above the anticipated soil level and near the center of the pot. Carefully add more potting material around the tuber to secure it in place, taking care not to bury the growing tip. If you did not use transplanting fertilizer, place one time-release Aquatic-Tab fertilizer pellet into the potting material on each side of the tuber.
If you are using garden soil, add a shallow layer of river or decorative rock on the surface to keep the soil in place. If you have large Koi, river rocks will help protect the tuber from being disturbed. Again, however, do not bury the growing tip.
Once you have potted your water lily, place it in an area of the pond that receives full sunlight. Carefully tilt the pot and slowly lower it into the pond. This allows the air bubbles within the pot to escape without dislodging the tuber. Placing a medium size rock on top of the tuber (do not cover growing tip) will also secure it in place temporarily. Remove the rock in a few weeks when the tuber is well-rooted.
Start young plants near the water surface, allowing only 6-10 inches of water over the crown. Lower them gradually as leaf stems lengthen. Keep a majority of the foliage at the surface when determining the depth of placement. Newly planted lily tubers may not flower for 6-8 weeks as they slowly develops roots. Flowering will also depend on the amount of sunlight and warmth received. In successive seasons blooms will become larger and more plentiful.
FERTILIZING YOUR LILIES
Water lilies are exceptionally heavy feeders. Fertilize monthly with Aquatic-Tab tablets during the spring and summer months. Or use the new Aquatic-Tab Spikes once in the spring to gradually release nutrients for the full season. Yellow leaves, infrequent blooms or slow growth usually indicate inadequate fertilization.
TRANSPLANTING MATURE WATER LILIES
Mature water lilies like to be somewhat crowded in their pots. However, if your lily has grown out over the side of its container and has roots dangling in the water, it is time to move it up one pot size. Use wide shallow water plant containers by Lerio, which have no holes, or European mesh baskets.
Lilies can be transplanted any time they are actively growing. Carefully remove the lily from the pot. The less you disturb the root-mass, the more quickly your lily will re-establish in the new container. Trim away any damaged or dead leaves. Use a knife to cut away any soft or rotted portions of the tuber. Sections of the tuber with no active growth can also be trimmed off.
Place the lily in a new container. If the new pot is deeper, add potting material under the lily to raise it to its original planting level. Continue filling in around the lily taking care not to bury the growing tip. For potting material selection and fertilizer instructions, see "Potting New Lily Tubers"
PROPAGATION & DIVISION OF TUBERS
Water lilies can be expensive to buy. If you have a mature specimen that is starting to out grow the pot, you may wish to propagate new plants from the old rootstock. Spring is the best time to divide lilies, as this gives the new plants plenty of time to establish themselves.
Propagation of the "Eyes"
Carefully remove the lily from the pot. Wash away the potting material from the tuber so that you can see it clearly. Some lilies produce small protruding bulbs or "eyes" with active growing tips along the body of the tuber. If your lily has developed eyes, these can be pulled or cut off and placed in small, no-hole pots or trays to grow and develop. They will need adequate light and warmth, so a greenhouse is the best place to grow the eyes until they are large enough to transplant as tubers. Otherwise you can leave them attached to the tuber to mature naturally and divide the main tuber as follows.
Division of the Tuber
Large lily tubers with multiple growing tips can be divided into sections. Each section must have both a strong growing tip and slender dark feeding roots. Wear gloves when handling lily roots, as some species can stain your hands. Using a sharp knife, cut the tuber into sections. Remove the long white anchor roots from the new divisions, making a clean cut close to the tuber. Leave the smaller feeding roots intact.
Trim away all large open leaves in the same manner. If left on they will make the newly planted tuber too buoyant. Do leave attached young foliage which has not yet unfurled. Follow this procedure on each new section. Now you are ready to pot the divided tubers.