B 413 L7 G7 opy 1 UNITED STATES DEPARTMENT OF AGRICULTURE I BULLETIN No. 962 Contribution from the Bureau o( Plant Industry WM. A. TAYLOR Chief JX.^ ^.-f*. JfW^^s7u Washington, D. C. PROFESSIONAL PAPER August 12, 1921 THE PRODUCTION OF THE EASTER LILY IN NORTHERN CLIMATES. By David Griffiths, Horticulturist. Office of Horticultural and Pomoloqical Investigations. CONTENTS. Page. The choice of method of propaga- tion 1 Production on a seedling basis 3 Production on a vegetative basis 16 Methods of propagation 21 Controlling bulblet formation 24 Soil for Easter lilies 24 Soil fertility 25 Page. Storage of bulbs 26 Sizes of merchantable bulbs 27 Varietal selections 28 The Easter lily in beds and borders. 29 Lengthening the flower season out of doors 30 Reducing the cost of heat in forcing. 30 Resistance to cold 31 THE CHOICE OF METHOD OF PROPAGATION. IT IS ASSL'MED that the grower of Easter lily stocks will start with seedlings. He may sow seed each season, but it is more likely that he will grow seedlings the first year and propagate vegetatively thereafter. When vegetative propagation is chosen the plants must be hardy enough to go through the winters safely out of doors. It has been amply demonstrated that the lily is sufficiently hardy in the latitude of Washington. D. C, to live through the winter either with or without a little mulch. The probability is that it will be found to be hardy very much farther north. If the grower goes back to seed each year it makes no difference whether the species is hardy in his locality or not, for the plants will not be in the open ground during the winter. The stock plants may be of any standard commercial variety, or any two standard varieties may be crossed. Good results have been obtained by cross-pollinating the varieties Giganteum and Har- 48307"— 21 1 v_\!rtA^ v^« 2 BULLETIN 962, l\ S. l^EPARTMEXT OF AGEIC'I'LTUKE. risii, Giganteiim and Formosum.^ or even two plants of any one of the above varieties, A trrower will succeed more often by pollinating one plant on to the other than by using only one parent plant, or. in other words, selfing or pollinating a plant with its OAvn pollen. It should be understood, however, that the basis of the stocks now grown by the Bureau of Plant Industry is selfed plants. But there was a delib- erate purpose in view in starting in this way. The set of seed was uniforndy small in nearly all of these selfs. Pollination should be performed as soon as the stigma is receptive and the pollen ripe. This stage can be determined by watching the anthers as the flowers open. When the flower starts to open, the anthers will usually be found with simply a slight crack along one side, exposing a narrow line of dusty yellow pollen. After a time, Avhich will vary with the light, temperature, and moisture conditions, the sides of this rupture Avill roll back, exposing the mass of dusty pollen over tlie entire surface of the anther. As soon as this condi- tion is evident the pollen should be transferred to the stigma which is to be fertilized. The time which it will take from the gaping of the flower until the stigma is receptive, i. e.. ready to l)e pollinated, will vary Avith atmospheric conditions. Under autumnal conditions in the greenhouse in cloudy weather it has taken '27 or :2S hours after the tube began to open before the stigma Avas receptive, while in the open in July flowers starting to open about sunrise were ready to be fertilized at or 10 o'clock. The grower will have to determine this period quite definitely. In general, it can be said that the stigma is ready to receive pollen as soon as its surface becomes glossy on account of the secretion of a viscid fluid, which in this lily is about the time when the edges of the anthers have rolled back and com- pletely exposed the yellow dusty pollen content. The sooner the pol- lination is done after these conditions obtain the better. The Easter lily may be gi-own under wide extremes of conditions, but it is difficult under conditions which might be termed inter- mediate. It seems to be a safe crop when properly handled in the climate of either Washin'gton. D. C. or the frostless Bermudas, but in the Gidf States it succumbs to the occasional low winter tempera- tures. This is not by any means without a parallel, the most strik- ing one. possibly, being the hardiness of the Concord grape on the Great Lakes and its tenderness to frost conditions in Florida, and is readily explainable by the fact that farther north the plants are dormant during cold weather, while in the intermediate region they ' The botanical name of the Easter lilj" is Liliiim lonniflonrvi. The above names desig- nate varieties which in commercial literature are usually referred to as here used with- out reference to their technical specific designation. L. lonfjWorum. LIBRARY-Of tONQ^ESS DOOUMENTfi DIVISION V -/ (jT V THE EASTER LILY IX XORTHERN CLIMATES. 3 \ V-* may be subjected to severe freezing; weather when in full vegetative vigor. There is evidence at hand that with care this lily may be grown much farther north in selected localities than has thus far been ad- vised. There is little doubt that in those northern regions where the snowfall is heavy and early, even though the temperatures be very low. it can be safely grown in the open ground. PRODUCTION ON A SEEDLING BASIS. GROWING THE SEED. Until such a time as the trade produces seed of the Easter lily and offers it for sale, it will be necessary for the grower to raise his own seed. The most feasible way to do this now is to procure imported bulbs either in the early winter, when they are generally offered for sale, or at Easter time, when most of the plants are in blossom, and grow seed for planting the following January. To insure a good set of seed it is necessar}^ to hand-pollinate each flower. (Fig. 1.) The blossoms are so large and their parts so con- spicuous, that this is a simple and easy task. Seed may be produced in limited quantity without this trouble, but in the greenhouse, espe- cially, the fertilization will be largely accidental and the set very poor or none at all. If it is the florist's object to cross particular varieties, care should be exercised that no pollen except that which is wanted gets on the stigma. It will be necessary to remove the anthers from the flower to be fertilized before they open and spread their pollen. If the plant which has been pollinated is set 2 feet or so away from others which bear pollen, it is ordinarily safe from contamination in the greenhouse. Usualh' the florist is not interested in following up a line of breeding, and all that he needs to do is to see that plenty of pollen is put on the stigma at the proper time. If pollinations are made at Easter, the seed will be ripe early in June. (Fig. 2.) NECESSITY FOR HAND POLLINATION. In the flower of the Easter lily the stigma is quite Avell isolated from the anthers. The action of the wind or other agency may cause the pollination of a flower with its own pollen. Avhich, of course, is the closest kind of selfing. Also, it is possible, when plants are grown in the open, that cross-pollination at times ma}' take place through the influence of insects and birds, but of this there seems to be little evidence. The necessity of hand pollination to obtain full fertiliza- tion consequently becomes apparent. Some seed will be obtained without anv attention other than allowing the flowers to wither nat- 4 BULLETIN 962, U. S. DEPARTMENT OF AGRICJULTURE. urally in the field, but a much better set can always be obtained by thorough artificial pollination. SELFED COMPARED WITH CROSSED PROGENIES. In the recent investigations made by the Bureau of Plant Industry iio attempt was made to obtain excessive vigor in the stocks handled. I'lG. 1. — roUiuating (hf JCastcr lily. The parts uf tlu- flowir an- so large that eveu the convpntional tweezers are disponsod with. Some years ago Mr. (Jeorge W. Oliver, Avorking on this subject under departmental auspices, developed some remarkably vigorous prog- enies by crossing the two commercial strains, Harrisii and Gigan- teum.^ Other investigators have obtained similar results by crossinir 1 Oliver, George W. The production of Easter lily bulhs in the United States. U. S. Dept. Agr., Bur. Plant Indus. Bui. 120, 24 pp., 4 pis. 1908. THE EASTER LILY IN NORTHERN CLIMATES. 5 the varieties Multiflorum and Harrisii. The profjjenies with which work has been done recently have as their basis selfed plants, i. e., those f)roduced from the pollen of a plant used on its own stigma instead of on the stigma of another plant of the same or a different variety. Subsequently, cross-pollinations of plants in the same lots have been practiced for the most part. Commonly, but not always, the set of seed in selfed plants is small as compared with that obtained when two plants of the same variety or of different varieties have been crossed. Flo. 2. — A crop (jf Easter lily seed being luoduicd in a greenhouse. LONGEVITY OF THE SEED. There is but little information as to the length of time that tlie seed of the Easter lily will remain viable after it is harvested. Ex- perience has shown that if planted as soon as it is gathered it takes about twice as long to germinate as when held and planted G months later. Perfect germination has occurred when the seed was 18 months old. This shows that perfect residts may be expected from seed held over to the second year. Whether seed can be safely held longer is not known. All the seed worked with in these investiga- tions was stored in paper sacks in the packing shed of an ordinary greenhouse. 6 BULLETIN 962, U. S. DHPAKTMEXT OF AGRICULTURE. PLANTING THE SEED. The time of planting seed will depend upon how the florist is going to handle his stocks, and possibly upon when his seed becomes avail- able. Sowing can be done at any season if suitable moisture condi- tions for germination are maintained. If seed is planted out of doors, it sliould be sown in late autumn for spring germination. For germination in flats, the usual compost of loam, sand, and leaf mold witli a very little well-rotted manure is preferred. Good suc- cess has been obtained Avith a variety of potting soils, even with quite heav}'' clays amelioraced with a little sand and i-ubbish. The best practice in sowing the seed is to fill the flat to the proper depth and strike the surface to a level. The seed is then scattered over this surface and pressed down rather finuly with a piece of board. The whole is then covered with one-eighth to one-fourth of an inch of fine soil sprinkled over the top. In out-of-door plantings it is better to put the seed three-fourths to 1 inch deep. HANDLING THE SEED FLATS. To the experienced plantsman the best direction that can be given on the subject of handling is "keep the flats in proper condition for germination." This condition does not differ for most seeds. Mois- ture should be kept at the surface constantly, but good provision for drainage should be made, so that the soil will never become water- logged. If it is not possible to keep the surface properly moist without it, a pane of glass can be laid over each flat, but if the moisture condi- tions of the greenhouse are as they should be this is not necessary. It will be all the better not to have had the glass on when the plants b.egin to come through, for at this time, especially if the plantings are thick, moisture and aerati(m must l)e carefully watched lest damp- ing-off occur. The flats after germination are preferably kept rather dry. Water- ing should be copious, Avith provision for rapid drainage, but at com- paratively infrequent intervals, so that the seedlings and the surface of the soil be not too wet. Clay seed pans can be used, in which case it will not be necessary to wet the .young foliage at all for a time. The time it takes for the seed to come up will vary greatly witli conditions. The first lot of seed produced in these experiments ripened in June. It required six or seven weeks to germinate when sown immediately after being gathered. The same seed planted the following January came up in three weeks. POTTING. The exact stage of growth at which Easter lily seedlings should be potted may vary considerably. Usually it lias i)een the practice THE EASTER LILY IN NORTHERN CLIMATES. 7 to transfer them to 2-inch pots when the second leaf was fairly well developed, although this has been done frequently when the first leaf was well straightened out. (Fig. 3.) It does not make much dif- ference which practice is followed. At whatever stage they are trans- ferred the plants seem to stand still for about three weeks after potting, and until the roots get out to the sides of the pot the top growth is always next to nothing; but after this the development is very rapid. Fig. 3.— a flat of .several lots of Easter lily seedlings ready to be potted. TRANSPORTATION OF SEEDLINGS. There is an opportunity for the development of a business in the production of 2-leaved or 3-leaved seedlings, to be furnished to florists or others to grow either in pots or in the open ground. Such seedlings might be sold either directly from the seed flats or, after being established, from a first shift. The plants are as easily transported in the 1-leaved to 3-leaved stage as at any other time. They have been shipped from Washington, D. C, to California in mail packages several times, and have arrived in perfect condition. One trial package in fine condition when it reached California Avas re- wrapped immediately and returned, but as it was not sufficiently protected from the cold it froze on the return trip. A successful method of packing is to lay down, first, a strip of paper, then on this a ribbon of moist sphagnum moss 2 or 3 inches wide. The seedlings are placed on the moss with the tops all one way 8 BULLKTIN m-l, V. S. DEPARTMENT OF ACiRICITLTURE. and extending beyond the sphagnum ribbon. They may be spread three or four or more deep, also in a ribbon, on the packing mate- rial. When all the seedling plants have been arranged and covered with a similar layer of sphagnum, the whole may be rolled up tight, the paper being tightly folded about the bottom and loosely folded around the top. The package should then be tied and i)acked in a strong container, so that it can not move. (Fig. 4.) Thus handled, Mie seedlings can be transported cheaply to any pai't of the country. TRANSFER TO THE FIELD. If the seed of the Kaster lily is sown about the 1st of January and potted in early March the plants will be ready to go into the open Fiu. 4. — Easter lily soedliugs iii isecoud loaf, showiiij; tli<- uii'thod of i);u'kiug adopted for shipment by mail. ground in late April or early IMaj', or when they will be safe from any inclement weather. They are then knocked out of the pots and planted without disturbing the ball of earth. There seems to be no checking of growth, the plants taking hold of the ground with no loss of time. When handled as stated, the 2-inch pots are well tilled with roots by the time the plants go into the field. It is therefore possible to knock the plants out and carry them to the field in flats, from which they are set with a trowel. THE EASTER LTI>Y IN NORTHKRX ( T.IMATES. 9 CONDITIONS IN THE FIELD. The experience of the Pmreau of Plant Tnchistrv with these lilies has been restricted to a heavy retentive clay soil ameliorated by the use of some sand and plenty of very rough stable manure. None of these stocks have as yet been grown on sandy soil. The seedlings have usually been set out in 3-foot beds 5 to 8 inches apart each way, which seems to afford ample space. Between the beds a 15-inch path has been left, which is also ample; a 12-inch path might 'e sufficient. After planting, it is desirable to work a little mulch of some suitable material between the plants to assist in preventing the ground from baking, preserving moisture, and keeping the soil cool. For this purpose sand and spent manure from sweet-potato beds, old manure, and even fresh very strawy manure have been used. The care of these plantings during the summer has consisted in keeping down the weeds by hand and watering during dry weather. In well- prepared soil, mulched with some debris, hand weeding is not a seri- ous matter. DEVELOPMENT DURING THE SUMMER. Lily plants set in the field from -i-inch pots in late April or early May will begin to throw up scattering stems in July, and some blos- soms will appear late in the month. These early-flowering forms w^ill be short, few flowered, and in general disappointing. As the season advances the stems become longer and bear a large number of flowers, but never are the plants in the field as tall as those in the greenhouse, although they often reach a height of 24 inches or more. ^Mien the time for frosts arrives there will be ijlenty of plants show- ing either flowers or buds to the number of three to seven, and in rare instances as many as a dozen. Possibly 25 per cent will have flowered, and the earliest will be maturing their seed, but most of the plants, nearly 75 per cent of them, will be in the form of large rosettes of basal leaves and plants which have started to form stems. REPOTTING FROM THE FIELD. Before there is daiigei- of severe frosts in autumn the lily seedlings should be repotted for winter flowering. The minimum temperature to which they should be subjected out of doors is about 28° F. The plants can be dug conveniently Avith a spading fork, ordinary care being used not to bruise them. (Fig. 5.) Most of the dirt is taken off the roots, and they are laid loosely in boxes, to be trans- ferred to the packing shed. Here within three or four days they are put into the smallest-sized pots into which they will go. Most of them, though, will have to go into 6-inch pots, for the reason that on 48307°— 21 2 10 BULLETIN 962, U. S. DEPARTMENT OF AGRICULTURE. account of the very large root system they can not be put low enough in pots of smaller size. There will be a goodly percentage of them, however, which can go into 4-inch and 5-inch pots. Whenever this is possible they should go into these small pots and be shifted to 6-inch pots when the smaller sizes are filled with roots. LOSS OF LEAFAGE IN REPOTTING FROM THE FIELD. It frequently happens that a goodly percentage of the bulbs, especially those whicli consist of the smallest number of basal leaves, lose all their leafage before they are placed in pots. No Fio. 5. — Digging Eastt-r lily seedlings in October, 1920. The seed was sown on No- vember 1, 1919. The plants are to be potted for winter flowering. Those which have not already flowered will be potted with the tops on and will not wilt. change in handling is necessitated by this loss, these bulbs being potted and treated precisely like the others. A most remarkal)le thing is the subsequent loss of leafage by the plants as they grow in the greenhouse. Those plants which are in the form of rosettes when repotted will in a few wrecks be seen to lose their lower leaves gradually, so that by Christmas there will be but little of the field leafage left. Of course, the leaves in this case are from bulb scales. The loss never simulates wilting or any other apparently unhealthy condition, but looks simply like a gradual ripening process. This loss of leafage is by no means confined to the scale leaves. The same loss takes place in the stem leaves of those plants which were THE EASTER LILY IN NORTHERN ("LIMATES. H in a more or less advanced stafre of stem development when repotted. The lower leaves gradually ripen and dry up in the same wa3% often leaving naked a few inches of the stem at the surface of the pot. This leaf loss takes place even when the plants have not been subjected to frost in the field. TRANSPORTATION OF NONDORMANT BULBS. The loss of the leaves naturally leads to the question whether it will be possible to produce seedling stocks, such as described, and transport them in autumn a reasonable distance to be repotted and forced. Experience this year seems to indicate that this can be done. Bulbs which had lost all their leaves were repotted and came right along in good shape, although in some cases they were not potted for four days after digging. It would not be surprising if it should be found feasible to w^rap the plants singly in paper in a butcher's package, even in the advanced rosette stage, and pack them tightly in boxes for shipment, but this has not yet been attempted. It should be noted that this is very different from the transporta- tion of dormant bulbs, although it may not at first seem very dif- ferent, especially when the seedling bulbs have lost their leaves. The bulbs referred to here, however, are in what might be called a vege- tative condition, in distinction from the imported bulb, w^hich is dormant. The imported bulb has a well-developed crown ready to go on and function the next season. The seedlings set out in May and dug from the field in a vegetative condition in October have a crowm also, but it is in process of growth and its growth will build up another crown for the next season's development about the time that the plant blossoms. The fact that the bulbs can lose all their leaA'es at potting time and still go on and function satisfactorily from the same crown seems to warrant the conclusion that they can be trans- ported safely for moderate distances. CARE AFTER REPOTTING. The plants are repotted from the field in all stages of development, from a rosette of basal leaves only to plants in full bud. (Fig. 6.) All can be potted in the same way and handled alike afterwards. It has been the practice to keep the pots on the benches in the green- house without heat from the time of repotting in October as long as the night temperature does not go below 40° F. As soon as there is necessity for heat a temperature of 45° to 50° F. is maintained at night until early December and then increased to a maximum of 60° F. The plants continue to flower during this period and from this time forward. 12 BULLETIN 962, U. S. DEPARTMENT OF AGRICULTURE. HANDLING PLANTS THAT HAVE FLOWERED IN THE FIELD. At difj^ing time the early seedlings (lig. 7) which have already blossomed in the field should be separated from the others and the stems cut off, but they can be potted like those which have not flow^ered and made to flower again by Easter, thus giving one small and one normal crop of flowers in 18 months from seed. The}^ require no different treatment from those Avhich have not flowered. However, if the florist desires, he can plunge them outside or treat them in all respects like imported bulbs. Fig. 6. — A group of sci'illiugs of the Ksistrr lily of the 1!)1U progeuy, selcctod from the field in late autumn to show diversity in development. Photographed a few days after they were potted from the field. AH are of the same age. GROUPING SEEDLING STOCKS. As the bulbs are potted from the field it is potssible to segregate them into five or more groups. One grou]) will be in full bud and will blossom within 10 days or two weeks. Another can be made to blossom for Thanksgiving, another for Christmas, another in Febru- ary, and the last for Easter. The last group -svill include the most backward of the plants in the field which have not flowered, together with the early-flowering forms Avhich are to blossom the second time. Of course, by holding them at different temperatures, all except those in bud, and possibly even those, can be made to blossom at the later date. THE EASTER LII.Y IX NORTHERN CLIMATES. 13 NATURE AND APPEARANCE OF THE SEEDLINGS REPOTTED FROM THE FIELD. As will be noted from the statements made on previous pages, the seedlings at potting time are exceedingly A-ariable, the greatest varia- tion occurring in the time at which they flower first, but there are also great differences of form aside from mere stature. (See fig. 6.) As has been stated, the early-flowering plants are short, 12 or 15 inches high, but those in full bud at repotting time are 2 to 2^ feet high and bear three to five flowers or more, while the first ones to open have one or two flowers as a rule. Fig. 7. — Easter lily seedlings. Seed planted January 1. lStl» ; pricked off in March ; set in the field May 1 ; blossomed in late July ; photographed October 6, 1919. Two of the bulbs are double nosed ; all are 6g to 8 inches in circumference. Below those showing buds there are plants in all stages of growth. Some have a few inches to a foot of stem with no buds showing, while others present a varying degree of basal leaf development with no signs of stem growth. It is in this late group, which has the most prolific development of basal leaves, that the grower will find the most robust plants and also the most floriferous ones. It is not at all uncommon for these, when the flower steni appears, to show very large ones bearing 8 to 15 flowers. Of all the field stocks thus handled, the preference is for the late- flowering forms, which bear a luxuriant growth of basal leaves, form- ing a large rosette at the surface of the ground at repotting time. 14 Bl'LLETIX W2, U. S. DEPARTMEXT OF AGRIt'ULTURE. These are invariably vigorous and productive. Each of these basal leaves in seedlings tips a bulb scale, and it is found that the plants which hold back and build up a large store by the development of an abundant strong basal leafage before throwing up their flower stalks are the strongest and most productive. The plants which have blossomed in the field are exceedingly in- teresting from the fact that they bear mostly double-nosed bulbs, which when potted will give at the second blossoming two stems bearing two to five flowers each. (See fig. 7.) Why this pre- ponderance of double-nosed bulbs occurs at this stage so promi- nently in field-grown seedlings is not entirely clear. The condition is more general than in pot-grown plants, i. e., those kept in pots in the greenhouse through their first flowering. It looks sometimes as though the stem in the field is of such great diameter as actually to force a separation of one side of the bulb from the other, thus compelling the formation of two crowns for the next season instead of one. as normally obtains in bulbs of the same size developed vege- tatively from small bulbs. BEHAVIOR OF THE SEEDLINGS AFTER REPOTTING FROM THE FIELD. The methods of handling the seedlings after they are repotted from the field have been considered under another heading. Their be- havior is most satisfactory. In two years' experience in handling them in this way they have never even appreciably wilted, although three or four days have sometimes elapsed between the time of dig- ging and the end of the potting. In the handling incident to the transfer from the field to the pots some and fre»|uently all of the leaves are broken off. for the basal leaves of seedlings, attached as they are to the tips of the scales, are quite brittle. There is, consequently, a goodly number of the bulbs which are entirely without leafage when ready to pot. No attention is paid to this, these bulbs being potted like the others. They in- variably come on again in fine condition from the same crown: in other words, they are not to be distinguished from the dormant im- ported bulbs except that they grow more rapidly. Strange as it may seem, these repotted seedlings, although moved with care and wilting but little, have to make in large measure a new root system after being potted from the field. Plants at all stages of growth, even up to full well-advanced buds which will open in 10 days, can be successfully repotted, but even these make an almost entirely new root svstem. For this reason it will not do to subject the plants to heat until the pots have filled with roots again, any more than it is permissible to subject poorly rooted imported bulbs to such treatment. This point should be kept in mind. The grower should realize that he can THE EASTEB LILY I^T [^sOETHERN CLIMATES. 15 not subject these vegetatively potted plants to heat at the same stage of top development as dormantly potted bulbs. He should remem- ber that these seedlings, which are all the way from large rosettes to plants in full bud and are perfectly " fit '^ in appearance, may have a great paucity of roots until new ones have had a chance to develop. It is not intended to give the impression that all the roots on plants which come from the field rot off. but many, and probably most of them as a rule, and often all of them. do. In spite of this loss and the additional loss of leaves which may or may not accom- pany it. the plants seem to recover and continue to grow until they flower in a perfectly satisfactory manner. TVliat probably occurs is a rejuvenation or reestablishraent of the uninjured roots and often of uninjured portions, all others decaying during the time that the plants are becoming established in the pots by the development of a new root system. There is need for careful investigation to determine to what extent the subsequent growth of plants would be injured by the complete removal of the root system when repotting them from the field while in vegetative condition. In the care of this lily the importetl bulbs always have their roots trimmed close, while an attempt is made with many lilies to save as much of the root system as is possible in handling. It will probably he much better not to attempt to set a time limit on the period required for the lily plants to reroot at a temperature of 40° to 50° F. at night. It will be much safer for the grower to de- pend upon the condition of the root system, which is most accurately gauged by an examination of the plant knocked out of the pot: The same conditions should govern the application of heat here as with imported stocks, with which the grower is familiar. TREATMENT OF SEEDLINGS NOT INTENDED FOR WINTER FLOWERING. The previous discussion is based on the assumption that the lily seedlings are to be brought into the greenhouse for their first flower- ing, or in the case of the early ones for their second flowering, upon the advent of cold weather in late autumn. If the intention, on the other hand, is to carry them out of doors, it will be realized that the plants are at two decided disadvantages with reference to the ap- proaching cold weather. In the first place, all plants that have not flowei-ed are going into the winter in full vegetative vigor and. in the second place, they are shallowly set on clean-tilled ground. Under such conditions in the climate of Washington. D. C, they may not winter successfully. A very heavy mulch of coarse material, such as cornstalks, might protect the bulbs sufficiently, but it is believed to be much the better method of treatment to dig and reset them at the proper level before the ground freezes in the fall. The digging can be done either before 16 BUTJ.ETIN {Xi2, V. S. DEPARTMENT OF AGRICXTLTURE, or after the tops are cut by freezing weather, but before there is (hmger of the ground freezing to any great extent. All the top growth should be cut off and the bulbs reset about 4 inches deep and mulched, preferabh- with an inch or two of manure, after the ground freezes a little. In the latitude of Washington, D. C, the digging and resetting can be done most advantageously about the 1st of November, when it is advised that dormant bulbs generally be planted. Handled in this way the seedlings will have a maximum period of development and will still have time to get a firm hold oii the soil before winter sets in. TREATMENT OF SEEDLINGS AFTER THEY HAVE FLOWERED IN THE GREENHOUSE. The disposition made of the bulbs after flowering will depend en- tirely upon circumstances. If the florist sells potted plants, that, of course, is the end of the transaction. He will then produce more seed and raise a new crop of seedlings for each winter's flowering, as described in previous pages. If, as is more likely the case in all middle latitudes, he wishes to work up stocks of vegetatively propa- gated bulbs to be handled like imported stocks, it will be necessar}' to preserve the bulbs as his potted plants flower. In this case, the flowers can be cut with short stems for formal pieces, or even with a foot of stem cut. The pots should then be kept rather dry and allowed to dry up completely within a month or six weeks. Any time after the 1st of April, or before if the soil can be worked, the bulbs can be planted in the open ground. The plants will blossom again in late July. In the fall they will be dug, the largest bulbs taken out for forcing or for sale, and the increase replanted in order to continue the outdoor growing. PRODUCTION ON A VEGETATIVE BASIS. PLANTING VEGETATIVELY PROPAGATED STOCKS. The previous pages deal with seedling stocks up to the time they are ready to be propagated vegetatively, as the Easter lily is usually produced. If these same stocks are to be grown continuously the handling must, of course, be modified. Normallj^ the lily bulbs will be planted in late autumn; but if the first-year seedlings have been flowered in thef greenhouse the bulbs will have to be planted out as soon as the ground can be worked in the spring. The character of the field planting will probably resolve itself into a bed eventually, mainly on account of the advantage of a mulch, which becomes an excessive burden in any but the most in- tensive fonn of culture. No better method of planting can be recommended than the Dutch bed, in which the planted space is 3 feet wide, with a 1'2-inch to 15-inch path between the beds. The bulbs are planted seven to nine or more to the row across the bed. (Fig. 8.) THE EASTEE LILY IN NORTHERN CLIMATES. 17 The bulbs should be separated into four or five sizes before plant- ing. In spring plantings of the seedling bulbs out of the house, two sizes will probably be sufficient ; for in this ease the bulbs will be large, with very little, if any, propagation. They will be simply the large seedling bulbs. Assuming that the rows are uniformly 6 to 8 inches apart, the larger of these sizes can be planted about seven to the row and the smaller nine to the row. They should be uniformly spaced and set up. After the seedlings have been grown outside for a year, however, there will be a large propagation of bulblets, and c(mse- quently it will be better to make four or five sizes. Fig. 8. — Bulbs being planted in a Dutch bed. In starting the planting on the bed plan, it is necessary to line out the beds carefully with taut lines, marked off by running a spade down 2 or 3 inches along the line and scraping the soil toward the center of the bed from either side. The soil is then thrown out of the first bed to a depth of about 4 inches and the bottom raked to a level. The bulbs are then set and spaced, as already described. The soil from the opening of the second bed is used to cover the bulbs in the first, and so on to the end of the plat. Figure 8 shows this method of planting the narcissus on Puget Sound and illustrates the opera- tion very well. After the first year there will be more than two sizes, as there will be plenty of stem bulblets at the next digging. It will then be neces- sary to plant a larger number to the row. One may have 14 and 21 18 BIJLLKTIN (K52, [\ S. DKPAnTAIEXT OF AOniCULTURE. to the row set up, and another size strewn along the row about one to the inch. The latter shoukl not be covered so deeply as the large bulbs. A modification of the above method of planting which obviates the moving of so much soil has pro\od satisfactory. The ground is pre- pared as before and preferably floated or rolled. Rows are then opened up lengthwise of the bed with a wheel hoe having a plow attachment. A row is opened and planted, and then the second row is opened ;.nd the first covered by the same operation. Five or six of these rows 6 to 8 inches apart are ])lanted ; then a row is skipped for a path and the next bed started. Either of these forms of setting gives a thick jdanting. which it is believed is the most economical of space, labor, and materials. TIME TO PLANT NORMAL VEGETATIVELY PROPAGATED STOCKS. In vegetative propagation the time of planting will always be late autumn, though the date will vary with the locality. There are two important requirements that should be met. The bulbs should be well rooted before the ground gets so cold that no growth can take place. On the other hand, they should be planted so late that top growth will not take place before winter. The grower should en- deavor to strike a balance between these two extremes, remembering that this lily does not stop groAving so long as the moisture and tem- perature conditions are favorable. It is this characteristic that makes the crop a precarious one on portions of the Gulf coast, where suit- able growing weather for it is likely to be interspersed with sudden drops of temperature which are severe enough to cut the top growth. In the climate of Washington, D. C, the best time to plant is about the first of November, Even at this late date the plants sometimes come through in very open winters and are somewhat yellowed by subsequent cold weather in early spring, but no injury has been apparent thus far, MULCHING, The matter of a mulch is of sufficient importance to be treated separately; indeed, it has sometimes seemed that a mulch expressed the difference between success and a large measure of failure in growing these jjlants under field conditions. The mulch serves a dual purpose. It is an adjunct to the fertilizer applied and a protective covering as well. The application should consist of an inch or two of manure. The material should be either fine or strawy and not cloddy, so as not to interfere with the plants coming through. The application should be made in early winter after the ground has cooled off sufficiently so that groAvth is stopped, and it should remain durinjj; the "frowiiiir season. THE EASTER LILY IN NORTHERN CLIMATES. 19 A summer mulch is considered as important in the culture of this lily as a winter one. Most lilies grow where there is a soil cover of some kind — many of them where this cover is a grassy one and others where the ground is just as effectively protected by brusii. under and between which the lilies grow, sticking their heads above the canopy to flower. Lilium longifor'um^ with the forms of which we are dealing, pro- duces a mass of roots from the stem above the bulb and near the sur- face of the ground. For the best results these roots, as well as those from the bulb, must have good conditions for development and must not be disturbed. This condition is admirably produced by a manure mulch, which not onh^ furnishes plenty of fertility but prevents the soil from drying out and baking and also equalizes its temperature to a remarkable degree. One should keep in mind that this lily, like most other lilies, likes to have its feet moist and cool and protected both summer and winter, but its head must be in full light. FLOWERING TIME FOR SEEDLINGS AND MATURE STOCKS. Attention has been called in a general way to the irregular blos- soming of a seedling generation. The experimental stocks in 1920, sown on November 1, 1919, began to flower in early July, at the same time as the out-of-door vegetatively propagated plants. The last of the progeny did not open its flowers before the end of May, 1921. All of these seedlings were kept under precisely the same con- ditions from the time of sowing the seed, and all operations, such as pricking off, potting, etc., were performed in as short a time as ordinarily would be possible. In spite of this identical handling, there was an extreme variation of 11 months in the time of flowering. In all progenies which have been grown in the last six years the behavior has been similar. When, however, these same bulbs have been handled normally for vegetative stocks, i. e., planted in No- vember, they have all flowered within a short space of time. (Fig. 9.) Two or three weeks cover the entire blossoming period, which is as close as would be the case with imported varieties grown out of doors in the same way. THE CUT FLOWERS. As in bulb culture, there is always a temptation to utilize the crop of flowers when there is sale for them. It has been found that it is practicable to cut off half of the stem in the first flowering of the seedlings in the greenhouse and still preserve the bulbs for start- ing vegetative propagation by planting out in the spring. The pots, after the cutting, are dried off rather quickly and the bulbs left in the soil until ready to plant out. There are no data on the compara- tive value of stocks thus flowered and those which have had their 20 BTLLKTIX !t