CULTURE OF THE TROPiEOLUM. 27 



those generally seen are seldom larger than a pigeon's egg — the largest we 

 have ever seen is one in our own possession, which is about the size of a 

 hen's egg. The growth of the plant is very delicate ; the stem very weak, 

 requiring daily attention in training; it attains the height of 12 to 14 feet, 

 but is oftener grown twined round a balloon trellis, which mode displays the 

 flowers and foliage to great advantage. A singular fact is noticeable in the 

 stem of this plant ; where it proceeds from the bulb it is very fine and hair- 

 like, but several feet from the bulb the stem is often very stout; this is to 

 be especially observed in those portions where the leaves are large and 

 healthy, which at once gives us the solution of the mystery. Does not the 

 plant derive the greater part of its nourishment through the leaves ? It 

 seems impossible that all can be derived through the delicate thread of 

 the stem, and a plant often twelve feet high, with thousands of leaves 

 and flowers, all be sustained by the sustenance which passes through so 

 small a medium. The question is one deserving attention. The plant is 

 propagated both by cuttings and seeds. The former is the most reliable, 

 but is liable to failure on account of the delicate nature of the plant ; the 

 cuttings in a majority of cases damping off. The soil to be employed in 

 striking cuttings should be pure sand, of the kind known as silver sand. 

 Seed is freely produced, but the outer covering is so hard that it generally 

 fails to vegetate ; the only way to secure success is to carefully remove this 

 hard shell, when the seed will easily germinate. This may seem doing 

 violence to nature, but it is a method which often has to be resorted to with 

 seeds of a tough integument. The general theory in the cultivation of all 

 species of bulbs is, that whatever tends to increase the size and vigor of 

 the bulb will have a corresponding effect on the growth of foliage and size 

 of flower. It has been discovered that roots are developed more rapidly, 

 and the size of the bulbs greatly increased, if, instead of planting the bulb 

 in the soil, the base is merely covered with earth and all the upper portion 

 left exposed. Great care must, however, be taken to avoid overwatering, 

 which is fatal to the health of the plant. The plants do not require very 

 large pots, for the growth of the root is not very luxuriant ; but care must 

 be taken to prevent the pots from being exposed to the direct rays of the 

 sun, and thus becoming heated, for the efiect of too much heat at the root 

 is at once apparent in yellow foliage and sickly flowers. We have seen it 

 recommended, and the idea is an excellent one, to place the pots containing 

 the bulbs in larger pots, the space between the two being filled with river 

 sand, which is kept constantly watered, and imparts a coolness and moisture 

 to the soil in which the plants are growing, which renders watering almost 

 unnecessiry. The above remarks will apply equally well to all the bulbous 

 Tropseolums, but especially to T. pentaphyllum, bracheseras, azureum, and 

 Jarrattii. Tiiis variety (T. tricolorum) is often attacked by red spider and 

 green aphis, but a little careful syringing and smoking will at once remove 

 these pests. The flower is too well known to need particular description. 

 The soil should be leaf mould, with a little sand ; we have noticed that 

 small bits of peat seemed to impart additional vigor; the earth should 

 never be allowed to become hard and sodden. 



