April i6, i*9 8 



GARDENERS' MAGAZINE. 



243 



SPONTAN 



HYBR 



OF HARDY PLANTS 



of the parent ; they seem to be intermediate with S. venusta, and are 

 graceful plants, superior to S. kamtschatica. 



!hed ^r^and seedlings are only weeded up when they become 



earden like that at Edge Hall, where hardy plants are allowed to Other hybrids of which I have established a stock are Aster Thorn- 



mix 



so thick or so large as to be obstructive, it is natural that many 

 accidental or spontaneous hybrids should be produced between species 

 having close affinity. But plants are curiously capricious in this matter ; 

 for we find that many which are closely allied both in appearance and 

 habit, never produce a cross, whilst there are others in the same genus 

 which cross so readily that the seed ripened in this garden can never be 

 depended upon to come true. For instance in the genus Dianthus, D. 

 alpinus and D. neglectus flowering together on the same rockery, do not 



whilst D. caesius and D. superbus, and some others are always 

 being transformed. Again I have never seen a cross between Scilla 

 sibirica and S. bifolia, which flower and seed by hundreds in the same 

 border ; but S. bifolia crosses abundantly with Chionodoxa Luciliae, In 

 others, as aquilegia, polemonium, verbascum, the tendency to cross 

 seems general. As regards the fertility of hybrids it is perhaps imprudent 

 to dogmatize ; though many are, as far as my experience goes, invariably 

 barren, polemonium, verbascum, campanula, papaver, belonging to 

 this class, whilst others are more or less sparingly fertile, though never 

 constant, either producing an ever- varying progeny, or reverting to one 

 or perhaps both of the parents. 



These hybrids of hardy plants generally have the merit of a prolonged 

 flowering season, and, in many cases, of greater vigour of growth and 

 facility of increase by division, than either parent, though it might be too 

 much to assert that this vigour lasts indefinitely, or that they have 

 a duration of existence to be compared to that of a species. It would be 

 difficult to prove this, because similar hybrids are probably produced 

 repeatedly, and duration of life only comes into the question where both 

 parents are perennial ; for, as far as I have observed, when the cross is 

 between a perennial and a biennial or annual the plant always follows the 

 shorter-lived parent. 



It is impossible in a short notice to speak of all the hybrids I have 

 noticed, but I give particulars of a few of them. All the perennial species 

 of polemonium seem to cross when grown near together. Perhaps the 

 most remarkable fact about them is the readiness with which P. flavum 

 becomes impregnated with the pollen of P. coeruleum, and the exactness 

 with which the seed reproduces the pollen parent, both with blue and 

 with white flowers. The type of P. coeruleum always has what is called 

 an ascending growth, whilst the hybrid has divaricate stalks ; but the 

 most obvious and certain distinction is the profuse seeding of the type, 

 and the sterility of the hybrid. Still, the characters so nearly resemble 

 those of the pollen parent that if I had not repeatedly satisfied myself 

 that the seed was produced by P. flavum, I should have thought it 

 incredible. P. reptans, P. humile, and the variety commonly called in 

 gardens P. Richardsoni, all intercross, and some of the results are very 

 neat and distinct border plants. To turn now to verbascum, the readi- 

 " e fs with which the Mulleins all cross is well known, and some of the 

 hybrids of biennial kinds are very beautiful, the various colours of V. 

 phocniceum being imparted to the tall branching habit of such biennial 

 species as V. Blattaria and V. Lychnitis, but these are only lucky acci- 

 dents, which cannot be artificially produced with any certainty as to the 

 result. However, crosses between V. phceniceum and V. nigrum produce 

 true biennials, varying widely in colour, and often having great merit, as 

 they send up a succession of profusely flowering spikes, and may easily 

 be perpetuated by dividing the root into) lengths ; still, their duration is 

 not for many years. 



soni with A. amellus, and A Thomsoni with A. pyrenaeus, both of merit, 

 both on account of their habit and elegance, and their flowering season, 

 which lasts from early summer to late in autumn. Both are entirely 

 barren, though I dare not assert that hybrids of asters, which come 

 abundantly in the garden are always barren. Columbines are plants of 

 which every species seems ready to cross with any other in the genus, and 

 the crosses are all fertile. Their flowers are supplied with pollen by the 

 bees as soon as they open, so that no species in the garden can be trusted 

 to reproduce itself, and they undergo from generation to generation end- 

 less changes. If, however, the best species, like A. cerulea, are not 

 frequently supplied, the stock has a tendency to deteriorate, and to be 

 merged into the strongest kinds, chiefly the old world A. vulgaris. By 

 eradicating the inferior flowers as soon as they show, and selecting the 

 finest for seed, a good strain is kept up, but the same plant will give seed 

 which produces both stubby short sparred and fine long-spurred flowers. 

 There is no space here to speak at length of hybrid primroses, and the 

 alpine primroses are not happy in the soil and atmosphere of this garden, 

 so get little attention, but many of the genus cross readily ; the wild 

 yellow auricula, and the self-purple kinds, probably P. viscosa, cross 

 readily, producing every variety of border auricula. P. rosea and P. 

 denticulata have also crossed, but the mixture was only fit for the rubbish 

 heap. I only mention one more hybrid in conclusion, a very pretty and 

 elegant plant, between Ranunculus amplexicaulis and R. gramineus. The 

 large flower, of citron colour, and the leaf and habit being in all respects 

 half way between the two. It is unfortunately of delicate growth, and 

 hardly seems likely to produce an established stock. 



Edge Hall, Malpas. 



C. Wolley DOD. 



Poppies sometimes produce interesting hybrids, not only the allied 

 rapaver onentale and P. bracteatum, which if grown from seed ripened 

 in me same garden produce an indiscriminate and intermediate but fertile 

 2^"° r ; ?• nudicaule, P. alpinum, and pyrenaicum, which also 

 fpriS are P erba P s onl y varieties of one type, so their crosses are 



mnrl ^ ° . Such dlstinct kinds as the tiny P. caucasicum, which has 



S a T W i n g ^ rden P roduced a cross w ith P. Rhceas, to die of 

 I haw °f ltS firSt flowerin &> and n ever producing a seed. But 



althnnai? J ?ry /°i? d P e / efinial h y brid P°PPy no * produced in my garden, 

 oXn nf P ^ thC i re ' fr T ° m S ? ed ^ iven me of P - rupifragum, fertilised with 

 anTZ^; °K ental \ It is intermediate in character, very ornamental, 

 BeW H y> emg abso . lut ely sterile, but increased slowly by division! 

 distort * S 1 ? lss 1 ln « P°PP ,es 1 should like to sa Y a word abou? the very 

 botaS ? Py "T 1 m S ardens as P. umbrosum, from the Caucasus, its 

 P RhcSs hTth i ^ mutatum > and k is now considered a variety of 



the mam/r 1 in ° u 8 h I havefor some years grown it in the same bed with ture advised awe, anu w« u, WM * ».u^ w B . rww «, - «~ 

 nevS n * Rhoeas > the two forms continue distinct, and I have time the plants are housed liquid manure may be given freely, as the 

 never been able to observe any intermediate characters. * " " J 



r9l 5 euch f e ? sanguinea has produced two 

 fact th n ;?I ° th ° f whichit is inferred to t 



obviouslvrrrnf^^rf? p ?- llen . parents grew at a distance. One is 

 green flowers Thil li K cylindrica, a species having rather large pale- 

 green thT!' 5 hybri ? has P ink flowers ' not without a suspicion of 

 late in'autn-n C i ar u P roduced plentifully all through summer and until 

 Pink flow Tk ♦ 1, U 15 good and inter mediate. The other has also 

 waspro^ of the P lant is more diffuse ; it 



leaved spede "J * P ° Uen ° f H " hispida ' ° r ° ne of the kindred dark " 



Potting v. Planting of Arum Lilies. 



The system of growing arums in pots the year round finds favour with 

 many who grow large quantities, and who require spathes at certain 

 seasons, commencing as early as possible. For many years we planted 

 out our arums, repotting them in the early autumn, and this system I 

 have advised in these pages for the production of especially fine spathes. 

 Needing a great many more plants than previously for decorative pur- 

 poses, and these in large batches, we have for the past two years fol- 

 lowed a different course of culture, growing arums always in pots, and 

 treating them more like bulbs than otherwise. The season for resting 

 arums will soon be at hand, so that my note will apply at this date. We 

 usually rest our plants from May to early July, and this is an important 

 part of their culture. The arums will have ceased to flower by the early 

 part of May, and it is advisable to rest them at that season if early 

 winter flowers are desired ; by feeding and abundant supplies of moisture 



arums may be had in bloom at midsummer, but I think at that season, 

 with a wealth of other flowers, they are unnecessary, while they are of 

 great value at Christmas and Easter. It is to the production of winter 

 spathes that my note refers. 



From the end of April or early in May for about six weeks or two 

 months our arums are placed in the open close together, much in the 

 same way one would treat pelargoniums after flowering, and treated thus 

 they lose many of the outside leaves. They are kept quite dry until pot- 

 ting time, and then the plants are shaken clear of the old soil and placed 

 in pots ; the largest roots will need eight-inch pots, as the growths are 

 nearly as thick as one's wrist ; there is the advantage in growing the 

 plants singly that they are then most useful for decoration, and can be 

 used to better advantage. The smaller plants go into smaller pots down 

 to five-inch sizes. I need not dilate upon composts, as nothing new can 

 be said, but it is well to pot firmly to obtain strong, sturdy foliage from 

 the start, as thick, leathery leaves are as important as spathes for 

 decoration. After repotting it is important to water carefully until 

 new roots are plentiful; and the plants well repay cold frame shelter 

 in rainy seasons, and growth is soon vigorous, and the plants should 

 stand on a warm border or be exposed to full sunshine, so that by the 

 middle of September they will be ready for housing. I have potted up 

 much earlier than advised, after a much shorter rest, and plunged the 

 pots up to their rims in an open border; this plan may with advan- 

 tage be carried out by those who object to severe drying off. There is 

 no difficulty in obtaining plenty of spathes for Christmas by the cul- 

 ture advised above, and this means much to many growers. Prom the 



distinct hybrids in Edge 

 be the seed parent, from the 



I have seen offered in 



nurseries hu resembles closely what 



fertile and^W nai 5 e ? f H ' brizoid es. Both these hybrids are sparingly 

 giant Soir ^ L 'J S ? if - ave Come up > but have not y et flowered. The 

 feet hieh it£ T u £ tlca ' which resembles a giant meadow sweet, eight 

 harden ' I beh .ave like a plant which produces no pollen in Edge 



pots will be full of roots, and the flower stems advancing. 



Take now the case of plants put out in borders in May or June 

 after flowering ; of course it is necessary to divide if the plants are to 

 occupy medium-sized pots when lifted, as they increase so rapidly that 

 the smaller growth greatly robs the flowering plants. Potting up being 

 done at the usual time, it is impossible to lift without breaking some 

 roots and there is thus a check ; indeed, I have seen plants flag badly, 

 for in some cases the ball of earth falls away from the roots, and for a 

 time the plants are busy making new roots, and so flowering is retarded. 

 I admit large individual spathes may be obtained from plants treated 

 thus and to many this may be an important point, but of course each 

 one must study his own wants. On the score of general utility, I am 

 strongly in favour of retaining the plants in pots all the year round, arid 

 drying off if large quantities of flowers are needed. There is also less 

 labour needed for this system, and to many this is a consideration ; the 



seed ; 



but 1 exarnmed tbe dry plumes without being able to find any one potting up suffices, whereas quite as much time is taken in planting, 

 i^iL^fy ev( r ry 7 ear two or three seedlings come up near it and potting up has still to be done. 



Syon Gardens. 



which every year two or tnre 



Ch have Produced pale-pink flowers, th 



ngs come up 

 e stature being hardly half that 



G. Wythes. 



