"The roses there, however, have not bloomed as they should have, except the seedlings of the Ross rose, and the new tender roses, and my Poly #1 rose. This is a polyantha hybrid that has fully a floriferous habit as any true polyantha, is nearly thornless, and needs no winter protection. Only occasionally does it lose a few inches off the tips. It grows more vigorously than polyanthas normally do, about 4 feet, and seems to be resistant to mildew and blackspot, and curculio. It may be susceptible to rust, but I am not sure of that. Does this description make you think it should be patented in the U.S.? To me, it is remarkable for the combinations of everblooming and hardiness. It is a pleasant pale pink, and there have already been some mutations to white. Its' only fault, "in my book" is that the spent flowers do not drop off, but have to be cut off. It is female sterile, and has very little pollen.
Poly #2 is much more colorful, a bright pink, and equally floriferous in June-July, but not everblooming on the old canes, tho' the new growths do bloom in the fall or whenever they terminate their growth for the season. It does not fade, but it is thorny. That sort of half-way to everblooming it shares with Rosa suffulta. If only #2 had the full everblooming habit, and were less thorny, it would be a prize.
I have a third polyantha hybrid and it just may be what I am looking forward to, except for the thorniness. But it was transplanted last fall, and I can hardly evaluate it this year.
Poly # 4 is a very tall grower, up to 6 or 7 feet, and the big bush with such small flowers looks odd. It is not as hardy as the others, but is too vigorous to be protected. All these came from pollen of Gloria Mundi on one of Simonet's hybrids of HT x laxa Retzius."

Personal correspondence - Percy Wright to Walter Schowalter July 10, 1979

It's highly unlikely Rosa laxa is in the parentage of 'Poly Won'. If it was, this cultivar would likely be vigorous and tall but it is quite short (60 cm) and lacks vigour. I suspect it is a selfed Polyantha cultivar.

"Then there is still another new rose that needs propagation and advertising - my Polly Won rose. It's a polyantha that is like F.J. grootendort, but almost completely thornless, more erect, hardier, and blooming even more freely in the fall, in fact as freely as Augusta. In addition it is free of all the rose diseases. Its only handicap is that the flower is somewhat too pale pink. I'd like to repeat the cross that gave me Polly Won (which is sterile both ways) but tho' I know the pollen parent I have forgotten the mother parent - except that it must have been a hybrid of Laxa Retzius."

Personal Correspondence - Percy Wright to Walter Schowalter - April 24, 1982

Named as the 'Polyantha that won' acc. to pers. corresp. to W. Schowalter [Pittao] Polyantha hybrid Pollen of 'Gloria Mundi' on one of Simonet's hybrids of a Hybrid Tea x R. laxa retzius; (corresp. to W. Schowalter) [Pittao} We are endeavoring to determine the parentage.