Liberty Hyde Bailey, Growing Cannas

MANUAL OF GARDENING
A PRACTICAL GUIDE TO THE MAKING OF HOME GROUNDS AND THE GROWING
OF FLOWERS, FRUITS, AND VEGETABLES FOR HOME USE
BY
L. H. BAILEY
SECOND EDITION
1910

Cannas are among the most ornamental and important plants used in decorative gardening. They make fine herbaceous hedges, groups, masses, and--when desirable--good center plants for beds. They are much used for subtropical effects (see Plate V).

Cannas grow 3 to 10 feet or more high. Formerly they were valued chiefly for their foliage, but since the introduction, in 1884, of the Crozy Dwarf French type with its showy flowers, cannas are grown as much for their bloom as for their foliage effects. The flowers of these new kinds are as large as those of gladioli, and are of various shades of yellow and red, with banded and spotted forms. These flowering kinds grow about 3 feet high. The older forms are taller. In both sections there are green-leaved and dark coppery-red-leaved varieties.

The canna may be grown from seed and had in bloom the first year by sowing in February or March, in boxes or pots placed in hotbeds or a warm house, first soaking the seeds in warm water for a short time or filing a small notch through the coat of each seed (avoiding the round germinating point). It requires two years to raise strong plants of the old-fashioned tall cannas from seed. Sow in light, sandy soil, where the earth may be kept at 70° till after germination. After the plants have got well up, transplant them to about 3 or 4 inches apart, or place in pots 3 inches wide, in good rich soil. They may now be kept at 60°.

The majority of cannas, however, are grown from pieces of the roots (rhizomes), each piece having a bud. The roots may be divided at any time in the winter, and if early flowers and foliage are wanted, the pieces may be planted in a hotbed or warmhouse in early April, started into growth, and planted out where wanted as soon as the ground has warmed and all danger of frost is over. A hardening of the plants, by leaving the sash off the hotbeds, or setting the plants in shallow boxes and placing the boxes in a sheltered position through May, not forgetting a liberal supply of water, will fit the plants to take kindly to the final planting out.

Plant out roots or started plants when there is no longer danger of frost. For mass effects, the plants may stand twelve to eighteen inches apart; for individual bloom twenty to twenty-four inches or more. Some gardeners plant them not closer than twenty to twenty-four inches for mass beds, if the soil is good and the plants strong. Give them a warm sunny place.

The old (foliage) sorts may be left out late to ripen up the fleshy root-stocks. Cut the tops off immediately after frost. The roots are safe in the ground as long as it does not freeze. Dig, and dry or "cure" for a few days, then winter them like potatoes in the cellar. It is a common mistake to dig canna roots too early.

The French sorts are commonly thought to keep best if kept growing somewhat during the winter; but if managed right, they may be carried over like the others. Immediately after frost, cut off the tops next the ground. Cover the stumps with a little soil and leave the roots in the ground till well ripened. Clean them after digging, and cure or dry them for a week or more in the open air and sun, taking them indoors at night. Then place them away from frost in a cool, dry place.