by me on December 20, 2009
It may even be necessary to keep the plant itself over the winter. This course is followed in case of seedling water-lilies which, during the year, have not advanced sufficiently to produce either seed or tuber. Though tubers have been formed, they may be immature and likely to decay before the next spring and it then becomes necessary to resort to other methods to retain the variety.
The experienced grower readily foresees which particular plant is liable to be in this undesirable condition in the fall and lays his plans accordingly. As soon as he has decided that the plant is worth keeping something which usually can be foretold in late summer – he digs it up and repots in a shallow box, five to six inches deep and about two feet square or even larger. After boxing, the plant is returned to the pond, where it will continue to grow until fall, at which time it can be transported bodily to a tank in the greenhouse. By keeping the water in the tank at ordinary greenhouse temperature, that is to say, 60° to 65° F., growth will not be interrupted, though somewhat retarded, and the tubers have an opportunity to mature. Following this method, it is highly probable that in the spring we will not only have the parent plant but likewise a number of small tubers, which will bloom the same season.
The temperature of the water in these growing tanks should be about the same as that of the house in which they are placed, that is to say, about 65° F. A little more heat is desirable for Nymphaea Sturtevantii, and a greenhouse pipe may be passed through the tank to supply the requirement. In an emergency, heating the tank with a coal-oil stove placed under it may be resorted to, but cannot be recommended as a general rule.
Keep the water level so that the edges of the pots are about two inches below the surface. When the leaves appear, keep them just floating, using blocks underneath to regulate the heights of the pots.
by me on December 16, 2009
Many hybrids are practically sterile, and must be propagated from the” roots.” The same method may also be used for the true species. Indeed, one can never depend on the purity of seed where several kinds have been grown in the same tank. Natural hybrids are common. For pure stock of tender water-lilies we must commonly have recourse to the following method, beginning a year in advance.
A young plant of the desired kind is kept all summer in a 6-inch pot, in very shallow water. It will make good growth for some time, and then all the leaves will die off. If this does not occur naturally, it must be induced in August or early September, by raising the plant to the surface of the water, or partly out.
When the leaves are gone, a tuber the size of a robin’s egg should be found in the pot. Now remove the pot from the water, and let it become nearly dry. Take out the tuber, place it in clean sand, and keep it in a moist, temperate, or warm greenhouse atmosphere until next March. Never let the tuber get hard and desiccated, nor should it get really wet. It needs only a gentle air-drying.
Now, to propagate, set pot and sand and tuber in a warm tank in March. The tuber should be planted about an inch deep. Soon a shoot comes out, sends up leaves to the surface of the water, and makes roots. When one good floating leaf is established, wash away the sand from roots and tuber, carefully break off the shoot with its roots from the apex of the tuber, and replant both plantlet and tuber. Of course the plantlet now goes into rich earth. The tuber should give off at least one more shoot. The first
plant is pushed forward for-flowering, the next is kept to form a tuber for the following year.
The easiest tender nymphaeas to grow, to keep over winter, and to increase from the tuber, are N. flavo-virens, N. Wm. Stone, and N. Mrs. C. W. Ward. The easiest to grow from seeds are the blue lotus, Zanzibar water-lily, and Nymphaea flavo-virens.