Society Bulletin No. 84, Sept. 1941
SOME HYBRID PEONIES
Arthur Percy Saunders
1. Albiflora X macrophylla (tomentosa)
This is a cross on which I began to work about 1918 and I have produced in all about 400-500 hybrid plants of this parentage.
Macrophylla is one of the earliest of all peonies; it comes into bloom in my garden usually during the first days of May while the Chinese peonies do not come in until June 5-10. This race of hybrids then gets a strong tendency to earliness from the macrophylla parent. They start to bloom about a week after macrophylla itself and then come scattering along until about the first of June. They are pleasant enough plants, but the blooms are too uniform in character to make the race a very exciting one. The flowers are almost always white or pale pink, single, and very moderate in size; also the plants are mostly quite dwarf, growing only two to two and a half feet high.
Out of all the seedlings I have had I have propagated only about half a dozen, the most distinctive being the variety to which I have given the name CHALICE. This bears white flowers 8-10 inches with a mass of long silky stamens which add greatly to the beauty of the flower. Another good one I have named SERAPHIM (formerly SERAPH). It is not quite so large as CHALICE, but it is a great bloomer and when at its best it is a striking plant. Another, called SEASHELL, is a pink single of very good quality. My preference in this race has been for the taller plants, the run of them being rather too dwarf.
Many years ago I made this cross using pollen of macrophylla on the Chinese peony JAMES KELWAY. Out of eight plants so produced three were double or semi-double. I lost one of these in transplanting, but the remaining two I have propagated and named, one of them, a pale pink being called AUDREY (formerly ROSALIND) and the other with some yellow in it, along with pink, CELIA. They are for their season very nice plants, and when well established they yield blooms that are almost fully double.
I have repeated the cross on JAMES KELWAY a number of times since, hoping to get more doubles, but I have never again had as good success as with the first crossing. However, in a recent group I have had one double that promises to be very good, perhaps the best of the lot.
I would recommend hybridists who want to get doubleness into their hybrid plants, and who are using Chinese peonies for one parent to make use of JAMES KELWAY or LADY ALEXANDRA DUFF for I have several examples of the tendency of these two plants to throw doubleness into their hybrid offspring.
The Chinese parent of CHALICE was PRIMEVERE, which I have used in a great many crossings, and with much satisfaction.
The cross using macrophylla pollen on Chinese peonies is not a difficult one; almost every bloom that is worked on will yield some seeds, provided the variety is itself a good seed-setter.
Most strains of hybrid peonies are sterile during the earlier years of their growth, and this strain follows the usual rule. However, after the plants have attained to full maturity they begin to set an occasional seed. I cannot tell how these seeds have been fertilized. It could be by the pollen of the bloom itself; or it could be by wind-borne pollen either from another plant of the same parentage or from anything else in the garden that was in bloom at the time. However that may be, these hybrids do acquire in time the habit of setting a few seeds, through never very many; and these seeds being viable we get from them plants which are the second generation from the original cross.
In these second generation plants there is a surprising change, for they have regained complete fertility. They have very strong pollen and are regular and fairly abundant seed-setters. Furthermore the plants themselves are taller than the first generation plants and altogether more finished and with much more style. It would be interesting to raise a large batch of third generation plants, and I am sure they would yield some fine things through the few that I have grown were not conspicuously better than those of the second generation. Limitations of space prevent me from growing such things in the quantity I would like, but anyone who wants to have the fun of growing an authentic strain of hybrid peonies without engaging in the rather exacting business of making his own crosses would, I am sure, be rewarded if he planted some of this second generation seed. Mr. Rex Pearce the seedsman, of Moorestown, New Jersey, now carries this strain of seed of mine, so it is available for anyone who wants it.
Among the hybrids of albiflora and macrophylla there have appeared a few rather amusing sports. Some are miniatures in every way—with small flowers only two or three inches across and with very small intensely glistening foliage; these plants are also very dwarf, being only about a foot high. Another curious form which appears occasionally is one in which the petals are star-shaped, only about half an inch wide, and in which the foliage appears curled and blistered.
When the reciprocal cross is made, i.e., with pollen of Chinese peonies used on macrophylla, there seems to be a strong tendency to doubleness. This cross takes badly and I have never had more than a few plants from it, but all of them have been double or semi-double. Another peculiarity of this group is their odor. They all smell of spices. Some of my visitors say nutmeg, some cloves, but all agree that the odor is very marked, very agreeable and very spicy. Now since macrophylla itself is without a very noticeable odor and the Chinese peonies, whatever odor they may have, do not smell of spices it is rather a problem where these hybrids get their odor from; all the more as the reciprocal strain in which albiflora is the seed parent never shows this character; nor do I possess any other peony that carries this odor except P. mlokosewitschi which does indeed come from the same geographical region as macrophylla but which is certainly not closely related to that species botanically. I was interested to read recently a description of the white peony from the island of Crete. This plant is to be called P. Clusii (T. W. Stearn, in an unpublished article), and in the description the flower is said to possess the odor of cloves!