This delightful and valuable plant bears itsand foliage from a rhizome. It is a plant which like the garden auricula is so often confined to the most impoverished and sunless corners of the garden that it is rarely seen at its best – and though so easy to bring into bloom indoors or in a warm or cold is all too seldom used in this way. For the market-grower it is a most valuable flowering plant for in some way it may be brought into bloom almost all the year round which, for the commercially-minded gardeners, means an income throughout the year, and at the same time fragrance in the garden and home.
A superstition has been handed down from early Victorian days that plants other than those recognized by our grandfathers as not conforming to the Victorian traditions of being true bedding plants in their sense of the word, should be planted in the most out-of-the-way places where they would not be too conspicuous. There they could bloom to their heart’s delight as long as they in no way interfered with the geraniums and the marguerites. And so our lovely native primroses and polyanthus and lilies of the valley spent their days struggling to catch a glimpse of the spring sunshine and competing with laurels and other too closely planted
shrubs for some small amount of sustenance from an all-too-often impoverished soil. And this is much how the lily of the valley has remained – because it will produce its fragrant bloom under the most adverse conditions no thought is ever given to what it can do under conditions that really suit it. Like the violet and primrose which are generally found flourishing in the partial shade of tall trees and in a moist soil rich in humus, it is thought that the lily of the valley, requiring much the same cultural conditions, will be equally happy planted in the impoverished soil of a town shrubbery or growing beneath ivy under a wall facing due north.
These are totally different conditions from the moist, humus-laden soil of a sparsely planted woodland, where the spring sunshine can penetrate to the full. Those who have grown polyanthus in aof undue shade and have then transferred the plants to an open, sunny situation with a soil rich in humus will be astounded at the difference. Exactly the same goes for the lily of the valley, or the convallaria as it is called in old gardening books. As one Victorian gardening authority described the treatment for this lovely plant, ‘they present no features of difficulty provided they are afforded a run free from invasion by more rapacious subjects, and that their vigour is sustained by judicious solicitude for their requirements in the way of nutriment’, which only shows how important it was in Victorian times to be a scholar in addition to being a gardener. But it is certainly true that the plant does require a nutritious soil and an unrestricted run.
PREPARATION OF THE GROUND
Occupying the ground for at least four years makes it essential that the plants are provided with a clean, deeply worked and liberally manured soil and one that is well drained and yet capable of retaining moisture. Unlike most bulbous plants, the lily of the valley enjoys a liberal amount of manure in addition to other humus-forming material in the form of decayed, spent hops or peat. Well-rotted stable manure is ideal and this should be well worked into the lower spit. If the land is heavy, add some weathered ash, some grit, or sand.
To the top spit, add as much available humus as possible all of which amounts to something very differ ent from the impoverished soil of the town shrubbery. I regret to say that I have yet to see a lily of the valley bed well cultivated and instead of producing large fronds or sprays of handsome-looking bells in profusion and over a long season, we see only those small, weakly sprays produced in very limited numbers. Little is done to correct such a state of affairs because presumably, few realize the huge difference between a well-grown plant and one so neglected.
The lily of the valley is a lover of potash which should be given in the form of wood ash which should be lightly forked into the soil after the ground has been prepared. If no ash is available, a 1-oz. per square yard dressing of sulphate of potash should be given. The ground should be prepared during early October and allowed ten days to settle down before planting about the middle of the month. An idealfor a bed is under a wall facing south or at the front of a shrub border where the sun can penetrate and where the shrubs will not compete for the food and moisture needed by the lilies.
But if beds are made under a wall or in the open ground where they may receive some shade from tall trees, they may also be covered with lights to bring the plants into bloom late in April, a month earlier than unprotected plants. ‘Valley’, as the plant is more commonly called amongst market salesmen, is exceedingly profitable during early and late spring and well worth growing in quantity for marketing the cut bloom. Lights will not only gently force thebut will keep the bloom in a clean condition so essential when used for bouquets. Hessian stretched over and round the beds will also help to keep the blooms clean, and unharmed by strong or cold winds.
Planting to fit the lights or to make picking and cultivation easy will be necessary. Never make the bed too wide. Those who wish to enjoy their ‘Valley’ over an extended period should plant in different aspects. The finest bloom and the most prolific too, will be from beds where the early summer sun penetrates, but themay be prolonged by planting a bed with a northerly aspect. The frame-covered plants will be in bloom late in April, followed by those in a sunny position in May and early June and then will come those from the northerly beds, which will continue the flowering into July. This is valuable where growing for market, for the florist or salesman appreciates a continuous supply of whatever produce is available – he can then build up a sound connection.
Ganwicks may also be used for covering the plants and here the plants should be set out in two trenches, allowing 6 in. between each. Preparation of the ground should be exactly as described the plants being set out about 8 in. apart, just as they would be in a bed. Too close planting is also a cause of failure with this plant, for in three years the bed will be a mass of roots which only compete with each other if planted too close, with the result that feware produced.
October is the best planting time and firm planting is desirable, but see that the top of the root is not set too deeply under the soil – it should be only just covered. Planting must be done when the ground is friable and in no way sticky. Unlikeand other similar roots, lily of the valley can be purchased in various sizes. ‘Young crowns’ as they are called in the trade, are suitable for flowering eighteen months after planting. Berlin Giant or Fortin’s Giant, will come into bloom within six months of planting. Those growing in frames would be advised to plant plump-flowering size crowns of one of the Giant varieties and to cover beds in alternate years to give the plants time to recover. Retarded crowns which have been held in cold storage, are used for maintaining a consecutive supply of bloom for greenhouse forcing. Their cost is about double that for best flowering size crowns but even so this line is most profitable, for greenhouse.
CARE OF THE BEDS
The first winter after planting and until the rooting system is formed, it is advisable to cover the beds with bracken. Afterwards, a mulch with decayed manure and peat should be given every October when the foliage has died down. I cannot recommend this mulching too often. It is so rarely done with any plant and yet how they revel in it. The mulch can be of decayed leaves or peat. Where manure has been scarce I have frequently used a mixture of sifted loam, peat and chaff, the leavings of a threshing-machine and with satisfactory results. But use something, even if it is chopped and wetted newspaper forked carefully around the plants. The mulch will protect in winter, retain moisture in dry weather, provide the new plant roots with something to get their teeth into, and if some rotted manure oris used, it will and fortify the plant. It will also smother weeds. Where a plant is being left undisturbed for a number of years and is expected to produce its quota of high-class blooms, a mulch is an essential part of the plants’ cultivations.
The plants should be lifted and divided only when necessary – if the crowns are given good cultivation throughout, the sign that they require lifting and replanting will be smaller flower sprays and this may not show itself for many years. It is unwise to disturb a bed that is cropping well, but should it become overcrowded and the flowers small, lift the plants in October, shake away most of the old soil, divide and replant into well-prepared beds again.
Of even greater importance to the market-grower will be the production of forced bloom, not only to supply the winter market with cut flower, but to market the crowns in bloom in 60-size. To follow on the frame and outdoor-grown bloom which will come to an end in July, retarded crowns may be brought into bloom early in October and continue until early January, while ordinary forcing-size crowns may be in bloom from mid-January until mid-April when once again frame plants will be in bloom. Thus, except for the late summer months of August and September there will be a continuous supply of bloom all the year round.
Retarded crowns which have been kept at a temperature of 18° F. for four weeks are generally planted about the first day of September. Deep boxes are generally used, but largeare also suitable, whilst for growing for sale in the pots, one of a size capable of producing a pleasing display will be suitable. The variety most suitable for retarding is Fortin’s Giant, which will be ready for four weeks after planting, provided high temperatures can be maintained. Successful forcing of ‘valley’ depends upon a high temperature and ample supplies of moisture.
This is not difficult during September and October, when the autumn sunshine will maintain a day temperature of up to 80 F. From November onwards a house temperature of about 70° F. must be maintained in a humid atmosphere provided by constant damping down. At all times, strong sunlight should be kept from the plants by stretching hessian above them. This will allow sunshine to warm the house without having direct access to the plants which must never be allowed to dry out. Moss and peat is generally packed around the crowns to prevent any drying out. This is augmented by some sand and mixed with a little finely sifted loam, the whole being quite tightly packed around the crowns which should be planted 1 in. apart. A 48-size pot will take eight crowns, a 60-size pot four or five crowns.
The roots should first be trimmed to 6 in. and afteror boxing should be placed under the greenhouse benches or in a mushroom house or any place where they may be kept quite dark and moist for two weeks or until the growth is about 5 in. high. Warmth, and darkness is essential. Then lift the plants to the benches where they may be given full light, but at all times a high degree of humidity and a high temperature must be maintained, except for the first two to three days after planting. Spraying of the foliage will be beneficial until the buds are beginning to open when overhead must stop. Lilies of the valley love liquid manure, both indoor and outdoor plants, and when coming into bloom a weekly application will in every way be of value.
Some staking of foliage and bloom will be necessary. Plants being grown for pot sale should have several wire sprigs inserted amongst the foliage or round the sides of the pot and a piece of green twine fastened round. Plants in boxes used for cut bloom should be retrained from falling over by inserting a few twigs amongst the foliage. The variety, Berlin Giant, is most frequently used for after-Christmas forcing. The crowns may be bought in from one of the several wholesale suppliers who ship the roots from Germany, or stock beds may be planted and should not be allowed to come into bloom the summer previous to forcing. The crowns are supplied with liberal quantities of liquid manure water throughout summer.
They are lifted during October after the foliage has died down and boxed or potted and placed in a frame. There they are covered with ashes and allowed to remain so until early December when they are taken to a greenhouse having a temperature of at leas. 60° F. They should be given the same treatment as for retarded crowns, grown on under humid conditions when they will be ready for picking mid-January. Where a temperature of about 55° F. can be maintained, pots of ‘Valley’ may be grown for market sale and for the home, where their fragrance will be much enjoyed. Growth will be slower under these lower temperatures but the plants will be more suitable for pot sale and will remain considerably longer in bloom. The crowns may be grown in a cold-house but they will not bloom until late in March, perhaps three weeks before those grown in frames, but at that time of the year the bloom will be most welcome in the home.
USING A HOTBED
A compromise may be made by using a hotbed covered with a frame. There the bloom may be obtained up to Christmas and early in March. The method is to prepare a hot bedby first rotting down straw or chaff with an activator. To this is added some peat or decayed leaves, some stable manure and a covering of poultry manure should be sprinkled over the heap as it is being built up. The whole should be turned twice in exactly the same way as for preparing a compost for mushroom cultivation. In a fortnight, when two turnings will have been given, temperatures of up to 140° F. will be reached.
The compost should then be bedded down and a 4-in, covering of soil and peat should be placed over it. Into this the crowns are planted with the tops just showing above soil-level. The frames are placed over the bed, canvas is stretched over to keep out strong light and by keeping the soil moist, humid conditions are maintained, while the manure should maintain a temperature of at least 60° F. if the beds are made up during late September. Hot water should be used for watering while soil should be heaped up round the outsides of the bed to keep the warmth from escaping. The plants will come into bloom early in November and if a second bed is made up three weeks later, a succession can be maintained up to Christmas. The used compost may be used for making up outdoor beds or for other bulbs which require manure.
The sprays are pulled rather than cut and before the top bells are opened. They should be in the green stage with the lower bells just opening. Tie into bunches of a dozen sprays backed with a couple of leaves.
After flowering, the crowns may be planted outside in beds liberally supplied with rotted manure and they should be fed with manure water for six months. There they will commence to bloom in eighteen months but they should not be used for forcing again.
CARE OF THE NEGLECTED BEDS
Beds of sadly neglected lily of the valley are to be found in most gardens. Most of them never bloom, those that do so produce no more than a odd spray of blossom. This state of affairs can be remedied by lifting the crowns, washing the soil from the roots and replanting into fresh beds suitably prepared. The work should be done during October, and throughout the following spring weekly applications of manure water should be given. There may be few, if any, blooms the first summer but a heavy mulch with peat and rotted manure during autumn should fortify the crowns for a bountiful show of bloom the following year.
Apart from the popular commercial forcing varieties, Fortin’s Giant, introduced from Paris, and Berlin Giant, which comes to us in regular supply from the Hamburg district of Germany, there is a rare double lily of the valley, known as Convallaria foreplena which carries an overpowering fragrance. It is extremely difficult to find and too expensive to use in quantity. There is also a delicate pink form which is quite inexpensive and is a most charming flower which should be more widely cultivated. It is just asas Convallaria majalis, the ordinary garden variety we know so well.
Convallaria is the correct name of Lily of the Valley, and this word is derived from the Latin, suggesting that the plant grows in valleys. This is a good indication of the preference of the plant for moisture and partial shade, although it will not succeed under waterlogged conditions.
Generously prepared sites enable the plants to continue to flower well over many years, and they need only be disturbed and thinned when they become really overcrowded. If the crowns are spaced 3 or 4 in. apart, they will have ample room to develop. It is most helpful to apply an annual top dressing of really decayed manure and compost material, when the foliage has died down in September. This treatment will ensure the continued production of really large bells instead of the small ones gathered from neglected plants. When picking the flowers, always leave at least one, since the foliage acts as lungs for the plants, and it is partially through the work of the leaves that the following year’s flowers develop or are prevented from forming.
Lily of the Valley respond well to forcing treatment. Theare packed closely in 6-in.-deep pots or boxes of sandy compost or peat and just the points left exposed. Plunged in leaf mould, sandy soil or fine weathered ashes, speedy rooting will occur. If the pots are then brought into a moist atmosphere where the temperature remains about 75-80° F., and kept from the light, they will soon push out their flower-spikes, being then brought into full light and given plenty of moisture. The temperature should be gradually lowered so that the growth remains strong.