SEPTEMBER
Sowing Sweet Peas — Autumn-sown annuals — Dahlias — Worthless kinds — Staking — Planting the rock-garden — Growing small plants in a wall — The old wall — Dry-walling — How built — How planted — Hyssop — A destructive storm — Berries of Water-elder — Beginning ground-work.
In the second week of September we sow Sweet Peas in shallow trenches. The flowers from these are larger and stronger and come in six weeks earlier than from those sown in the spring; they come too at a time when they are especially valuable for cutting. Many other hardy Annuals are best sown now. Some indeed, such as the lovely Collinsia verna and the large white Iberis, only do well if autumn-sown. Among others, some of the most desirable are Nemophila, Platystemon, Love-in-a-Mist, Larkspurs, Pot Marigold, Virginian Stock, and the delightful Venus's Navel-wort (Omphalodes linifolia). I always think this daintily beautiful plant is undeservedly neglected, for how seldom one sees it. It is full of the most charming refinement, with its milk-white bloom and grey-blue leaf and neat habit of growth. Any one who has never before tried Annuals autumn-sown would be astonished at their vigour. A single plant of Nemophila will often cover a square yard with its beautiful blue bloom; and then, what a gain it is to have these pretty things in full strength in spring and early summer, instead of waiting to have them in a much poorer state later in the year, when other flowers are in plenty.
Hardy Poppies should be sown even earlier; August is the best time.
Dahlias are now at their full growth. To make a choice for one's own garden, one must see the whole plant growing. As with many another kind of flower, nothing is more misleading than the evidence of the show-table, for many that there look the best, and are indeed lovely in form and colour as individual blooms, come from plants that are of no garden value. For however charming in humanity is the virtue modesty, and however becoming is the unobtrusive bearing that gives evidence of its possession, it is quite misplaced in a Dahlia. Here it becomes a vice, for the Dahlia's first duty in life is to flaunt and to swagger and to carry gorgeous blooms well above its leaves, and on no account to hang its head. Some of the delicately-coloured kinds lately raised not only hang their heads, but also hide them away among masses of their coarse foliage, and are doubly frauds, looking everything that is desirable in the show, and proving worthless in the garden. It is true that there are ways of cutting out superfluous green stuff and thereby encouraging the blooms to show up, but at a busy season, when rank leafage grows fast, one does not want to be every other day tinkering at the Dahlias.
Careful and strong staking they must always have, not forgetting one central stake to secure the main growth at first. It is best to drive this into the hole made for the plant before placing the root, to avoid the danger of sending the point of the stake through the tender tubers. Its height out of the ground should be about eighteen inches less than the expected stature of the plant. As the Dahlia grows, there should be at least three outer stakes at such distance from the middle one as may suit the bulk and habit of the plant; and it is a good plan to have wooden hoops to tie to these, so as to form a girdle round the whole plant, and for tying out the outer branches. The hoop should be only loosely fastened—best with roomy loops of osier, so that it may be easily shifted up with the growth of the plant. We make the hoops in the winter of long straight rent rods of Spanish Chestnut, bending them while green round a tub, and tying them with tarred twine or osier bands. They last several years. All this care in staking the Dahlias is labour well bestowed, for when autumn storms come the wind has such a power of wrenching and twisting, that unless the plant, now grown into a heavy mass of succulent vegetation, is braced by firm fixing at the sides, it is in danger of being broken off short just above the ground, where its stem has become almost woody, and therefore brittle.
Now is the moment to get to work on the rock-garden; there is no time of year so precious for this work as September. Small things planted now, while the ground is still warm, grow at the root at once, and get both anchor-hold and feeding-hold of the ground before frost comes. Those that are planted later do not take hold, and every frost heaves them up, sometimes right out of the ground. Meanwhile those that have got a firm root-hold are growing steadily all the winter, underground if not above; and when the first spring warmth comes they can draw upon the reserve of strength they have been hoarding up, and make good growth at once.
Except in the case of a rockery only a year old, there is sure to be some part that wants to be worked afresh, and I find it convenient to do about a third of the space every year. Many of the indispensable Alpines and rock-plants of lowly growth increase at a great rate, some spreading over much more than their due space, the very reason of this quick-spreading habit being that they are travelling to fresh pasture; many of them prove it clearly by dying away in the middle of the patch, and only showing vigorous vitality at the edges.
Such plants as Silene alpestris, Hutchinsia alpina, Pterocephalus, the dwarf alpine kinds of Achillea and Artemisia, Veronica and Linaria, and the mossy Saxifrages, in my soil want transplanting every two years, and the silvery Saxifrages every three years. As in much else, one must watch what happens in one's own garden. We practical gardeners have no absolute knowledge of the constitution of the plant, still less of the chemistry of the soil, but by the constant exercise of watchful care and helpful sympathy we acquire a certain degree of instinctive knowledge, which is as valuable in its way, and probably more applicable to individual local conditions, than the tabulated formulas of more orthodox science.
One of the best and simplest ways of growing rock-plants is in a loose wall. In many gardens an abrupt change of level makes a retaining wall necessary, and when I see this built in the usual way as a solid structure of brick and mortar—unless there be any special need of the solid wall—I always regret that it is not built as a home for rock-plants. An exposure to north or east and the cool backing of a mass of earth is just what most Alpines delight in. A dry wall, which means a wall without mortar, may be anything between a wall and a very steep rock-work, and may be built of brick or of any kind of local stone. I have built and planted a good many hundred yards of dry walling with my own hands, both at home and in other gardens, and can speak with some confidence both of the pleasure and interest of the actual making and planting, and of the satisfactory results that follow.