A few flowers of this beautiful plant occasionally appear as a novelty in the windows of some of the best flower stores. It is certainly a novelty, too, in the cut flower market, though far otherwise as a cultivated plant, having been in cultivation for more than 100 years. It was introduced to Europe from the Cape of Good Hope in the latter part of the eighteenth century and has become so completely naturalized upon some lakes and streams as to appear like a native, so great is its luxuriance.
Doubtless much might be done with it in American waters in southern latitudes, but the present object of this note is to advise those who have the facilities to give it a little attention under glass for winter flowering, and small indeed are its cultural needs. Grown under glass it would be an ever-blooming plant as in outside waters it flowers persistently till forced to a reluctant rest by the freezing of the water.
I have gathered flowers of it in midwinter when that season has been unusually mild, so that no forcing conditions are necessary under glass to insure flowers in abundance during winter months. Tanks, tubs, or any receptacle of sufficient size and convenience could be utilized for its cultivation, placing in the bottom of them about a foot of compost consisting of loam and well rotted cow manure in proportions of about three to one The temperatures at which rose and carnation houses are kept will suit admirably and like these the aponogeton will enjoy all the sun it can get. As far as my observation goes of the plant under natural conditions it always appeared to thrive best and flower most abundantly along the margins of running water or in lakes through which there was a constant flow. This would indicate that it likes a change of water more or less frequently, conditions that can be met under cultivation by turning the hose into its tank or tub occasionally. The plant has a fleshy tuberous root, broad and flat at its apex, narrowing to almost a point at its base, and from the crown of this tuber it sends out long roots in the soil surrounding, while the leaves and flower stalks find their way to the surface, each stalk terminated by an oblong leaf that floats on the water.
The flowers are borne on a forked spike (hence the name distachyon, meaning two-spiked), are small and inconspicuous in themselves, but they are disposed in clusters in the axils of large showy white bracts. These bracts give the spike its color attractiveness, but the flowers have also a welcome charm in that they possess a delightful fragrance so sweet as to have earned for the plant the name of water hawthorn. The Cape pond weed is another popular name for it and it matters not which is used, either being greatly preferable to its botanical cognomen, and should be used by those who would popularize the plant and sell its flowers.
When once the plant is strongly established it spreads freely by root increase and also reproduces itself from its own self-sown seed. Dry roots are also obtainable at times, these being imported from the Cape. The beginner with dry roots, however, must exercise caution in starting his plants, otherwise he may lose the lot. When the dormant tubers are potted up they are dry and more or less shrivelled. If then introduced to aquatic conditions there is a risk of the root tissues swelling too rapidly and rotting in consequence. It is better for a start to treat them as ordinary plants, planting the tuber, with its crown just covered in a pot of soil. It will then absorb moisture gradually, swell normally and when top growth is visible and well under way the plants may be immersed with safety. When new plantations are being established with divisions from growing plants no such precautions are necessary; these can be planted direct into other tubs or tanks.