‘Keessenii’ 
‘Kempferi’ 
‘Knap Hill Form’ 
‘Knaphill Buttercup’ 
34 
(W. Keessen, Jr. & Zonen, Terra Nova Nursery, Aalsmeer, Holland. Catalog, 
p. 37. 1911, as P. coccinea lalandei ‘Keessen’ [not seen]). B.K. Boom. 21st 
Jaarboek, Nederlandse Dendrologische Vereniging (1956, 1957, en 1958), 
pp. 152-153, 155. 1959, as P. coccinea cv. ‘Keessen’ (Keessen) : Spread- 
ing shrub, twigs pubescent; leaves oblong, blunt, rounded teeth; fruit 
orange red, flattened, about 10 by 7 mm, ripening in September; moderate 
hardiness; scab susceptible. Selected by W. Keessen, Terra Nova Nursery, 
from plants of ‘Lalandei’ planted in 1890 by L. Springer at factory in 
Helmond, Holland. B.K. Boom. Nederlandse Dendrologie, 4th ed., p. 265. 
1959 : Shoots pubescent; fruit flattened, 10 by 7 mm; found 1891 in The 
Netherlands. G. Kriissmann. Handbuch der Laubgehélze, vol. 2, p. 287. 
1961 : Fruit broad, cone shaped, 10 mm thick, 7 mm high; selected in 
1891 by W. Keessen, but introduced as ‘Lalandei’. D.R. Egolf and R.F. 
Drechsler. Baileya 15(2):84. 1967 : Chromosome number 2n=34. 
Misspelled as ‘Keesen’, ‘Keesseen’, ‘Kessen’ 
P. coccinea 
Orange 30B, RHS 
(M.E. Mathias and E. McClintock. A Checklist of Woody Ornamental 
Plants of California, p. 48. 1963, without description). Letter June 28, 
1974, Paul von Kempf, Pacific Coast Nursery, Colma, California : Chance 
seedling selected and named by Heinrich Edler von Kempf, Pacific Coast 
Nursery, in the 1920's; original plant lost; nursery stopped growing this 
selection in 1947 or 1948. 
(C. Philip, compiler. The Plant Finder, 4th ed., p. 383. 1990, without 
description) : As available from Perryhill Nurseries, Hartfield, Sussex, 
England. Letter July 17, 1990, P.J. Chapman, Perryhill Nurseries : Name 
listed in The Plant Finder [Philip 1990] is in error. 
= ‘Knaphill Lemon’ 
(Knap Hill Nursery, Woking, Surrey, England. Catalog, p. 3. 1948-49) : 
Fruit buttercup yellow, profuse. Geo. Jackman & Son, Woking, Surrey, 
England. Catalog, p. 51. 1953-54, as P. rogersiana ‘Knaphill Buttercup’ 
