Part 26 (1/2)

Both the double and the single cla.s.ses of Dahlia are increasingly grown as annuals from seed, and this practice has the great advantage of being economical in time and in the saving of s.p.a.ce during winter. The seedlings grow freely and quickly, and will flower quite as early as those grown by the more lengthy and troublesome method from tubers. Even those who possess a stock of named sorts may with advantage raise a supply from seed, especially as there is a probability of securing some charming novelty, which is in itself no small incentive.

Although the Dahlia is a tender plant, it is easily managed in a greenhouse, or in a frame resting on a hot-bed. The seed may be sown as early as January, but unless sufficient s.p.a.ce is at command to keep the plants stocky as they develop, it will be wise to wait until February. A sowing in the month last named will produce plants forward enough to bloom at the usual time. Even March will not be too late; but whatever time may be chosen, when the start has been made it must be followed up with diligence, so as to avoid giving any check from first to last. Sow thinly in pots or pans filled with ordinary light rich compost, and cover the seed with a mere sprinkling of fine earth. When the first pair of leaves attain the height of an inch, pot off each plant singly close up to the base of the leaves. It is not advisable to throw the weakly seedlings away; these are the very plants which are most likely to display new shades of colour and they are worth some additional trouble.

Although weak at the outset, they may, by judicious treatment, be developed into a thriving and healthy condition.

When potted, place the plants in heat, giving a little extra care until growth is fairly started. In due time s.h.i.+ft into larger sizes as may be necessary, and then it will be wise to consider whether there is s.p.a.ce to grow the whole stock well. If not, do not hesitate to sacrifice the surplus, and in doing so reject the rankest-growing specimens, for these are least likely to produce a fine display of bloom. It is mistaken practice to take out the top shoot, as this checks the plant for no good end; but when about six inches high, each one will need the support of a stick. Give water freely, and air on all suitable occasions. The least tendency to curled leaves indicates something amiss, and demands immediate attention. A cold blast may have stricken the plants, or the soil may be poor; lack of sufficient water will produce the mischief, or it may arise from the presence of aphis. If the last-named a.s.sumption prove correct, fumigate on the first quiet evening, and omit watering on that day. The mere mention of the other points will be sufficient to show the remedy for them.

As the time for transfer to the open air approaches, all that is possible should be done to harden the plants for the change. They may be placed for a few days under the shelter of a wall or hedge, but on the least sign of frost be prepared to protect with hurdles or mats. Full exposure during genial showers and fair weather is advisable, and an occasional examination of the plants will prevent their rooting through the pots into the soil.

The border for Dahlias can scarcely be made too rich, for they are hungry and thirsty subjects, and will amply repay in a profusion of bloom the manure that may be lavished upon them. Slugs and snails are unfortunately too partial to newly planted Dahlias, but the vermin soon cease to care about them; therefore it is advisable to plant Lettuces plentifully at the same time, or previously, on the same ground, and to dust around the Dahlias with lime. Insert at least one stake, about a yard long, near each plant, to give support, and two or three others will have to be given before the branches spread far. Secure the first shoot when planting is completed, and follow up the tying as growth demands.

Dahlias bloom continuously for a long time, and appear to be especially at home in the shrubbery border, or in the centre of a bed. They are also valuable for training against buildings having a southern aspect, and here the flowering period is much prolonged, for an early frost will scarcely reach them. A light wall is an admirable background for deep-coloured varieties, and the white or yellow flowers are displayed to advantage against a dark building. Dahlias may be used either alone or in company with the climbing plants which are usual in such positions.

The flowers possess a special value for indoor decoration, and any odd corner of the garden can be utilised for producing a supply for this purpose. Cutting should invariably be done in the early morning, while yet the dew is upon them. They will then retain their beauty for a longer period than those taken at a later hour from the same plants.

This remark is true of all flowers, but it applies with especial force to the Dahlia.

==DAISY, DOUBLE==

==Bellis perennis fl. pl. Hardy perennial==

The remarkable development of the Double Daisy in recent years has raised this simple garden subject to the foremost rank of spring bedding plants. So p.r.o.nounced has been the improvement achieved in the size and form of the flowers, that plants raised from a reliable strain of seed will now produce blooms which may well be mistaken for specimens of finely shaped Asters. When ma.s.sed in a large bed the flowers present one of the most striking sights to be seen anywhere in the spring garden.

But apart from their use in formal beds and borders, Double Daisies make a pleasing break among Wallflowers, and are particularly attractive when grown as an edging to bulbous flowers and other spring-blooming subjects such as Polyanthus, Myosotis, &c. Plants from a sowing made in pans in April and put out when large enough, may be flowered in the autumn of the same year. But the method more generally practised is to sow on prepared beds in the open during June or July, and to transfer the seedlings when sufficiently developed to positions for blooming in the following season.

==DELPHINIUM==

==Hardy perennial==

Nearly all the perennial varieties may be raised from seed, and where large numbers are required this is the best method of obtaining them.

They make handsome border flowers, and are extremely valuable during the early months of summer. Sow in May, June or July, in the open ground, and transplant in autumn. If mixed seed has been sown, it will not be wise to thin out all the weakly plants, or it may happen that some of the choicest shades may be lost. The first flowers will be over by midsummer, but if the stalks are promptly cut down instead of being allowed to seed, there will be a second display later in the year.

Three varieties, Queen of Blues, Dwarf Porcelain Blue, and Blue b.u.t.terfly, may be flowered as annuals, by sowing in pans in March and transplanting to the open as soon as the seedlings are ready. They also make particularly charming pot plants, for which purpose it is advisable to sow seeds in March.

The scarlet variety (=D. nudicaule=) is rather more delicate than the others, and it is wise to raise the plants in well-drained seed-pans, and to take care of them through the first winter in a cold frame; indeed, in a heavy soil there is a risk of losing them in any winter which is both cold and wet. It is not necessary to employ pots, but immediately after flowering take them up and store in peat until the following April, when they can be returned to the open ground.

=D. sulphureum.= The seed takes a very long time to germinate, and severely taxes the patience of the sower. But otherwise there is no difficulty in raising plants, and the long spikes of beautiful clear sulphur-yellow flowers are well worth the extra time the seedlings need.

The best plan is to sow in autumn in the open ground, cover with a frame, and avoid disturbing the soil, except for weeding, until the next autumn, when the plants should be put into position for flowering in the following summer.

As slugs are exceedingly partial to Delphiniums, the crowns should be examined in spring, and the seed-beds may be dressed with soot and surrounded with ashes to save the seedlings from injury.

The annual Delphiniums are dealt with under Larkspur, page 274.

==DIANTHUS==

==Pink. Biennials, hardy and half-hardy==