A new and distinct Philadelphus cultivar named ‘W1’ is disclosed, characterized by a compact habit, and large, clear white flowers with a strong, sweet scent. The new variety is a Philadelphus, normally used for outdoor ornamental purposes.

Latin name of the genus and species:Philadelphussp.

BACKGROUND OF THE INVENTION

The newPhiladelphuscultivar is a product of a planned breeding program conducted by the inventor in Hampshire, United Kingdom. The objective of the breeding program was to develop large flowers with a nice, strong scent, and clear white flower color. The open-pollination resulting in this new variety was made during 2014.

The seed parent is the unpatented varietyPhiladelphus maculatus‘Sweet Clare’. The pollen was taken from several unnamed, unpatented proprietaryPhiladelphusseedlings. The new variety was selected in 2018 by the inventor in a group of seedlings resulting from the 2014 crossing, in a nursery in Hampshire, United Kingdom.

Asexual reproduction of the new cultivar was performed by softwood cuttings. This was first performed at the same nursery in Hampshire, United Kingdom in 2018, and has shown that the unique features of this cultivar are stable and reproduced true to type in multiple successive generations.

SUMMARY OF THE INVENTION

The following traits have been repeatedly observed and are determined to be the unique characteristics of ‘W1’ These characteristics in combination distinguish ‘W1’ as a new and distinctPhiladelphuscultivar:1. Relatively large flowers.2. Clear white flowers.3. Compact size.4. Floriferous.5. Strong, pleasant floral scent.

PARENT COMPARISONS

Plants of the new cultivar ‘W1’ are similar to plants of the seed parent in most horticultural characteristics; however, plants of the new cultivar ‘W1’ differ in the following;1. Flowers of the new variety are on average 3.2 cm in diameter; flowers of the seed parent are on average 2.5 cm in diameter.2. Flower color of the new variety is fully white, while flower color of the seed parent is white with a pink heart.3. Fragrance of the new variety is more pleasant than the fragrance of the seed parent.

The exact pollen parent cannot be identified.

COMMERCIAL COMPARISONS

Plants of the new cultivar ‘W1’ are comparable to the commercial varietyPhiladelphus‘Belle Etoile’, unpatented. The twoPhiladelphusvarieties are similar in most horticultural characteristics; however, the new variety ‘W1’ differs in the following;1. Flowers of the new variety are fully white, while flowers of this comparator are white with pink centers.

Plants of the new cultivar ‘W1’ are comparable to the commercial varietyPhiladelphus‘Snowwhite Fantasy’, U.S. Plant Pat. No. 13,774. The twoPhiladelphusvarieties are similar in most horticultural characteristics; however, the new variety ‘W1’ differs in the following;1. Flowers of the new variety are single, while flowers of this comparator are double.2. Flowers of the new variety have fewer petals than flowers of this comparator.3. Leaves of the new variety are smaller than leaves of this comparator.

Plants of the new cultivar ‘W1’ are comparable to the commercial varietyPhiladelphus‘Dainty Lady’, U.S. Plant Pat. No. 24,536. The twoPhiladelphusvarieties are similar in most horticultural characteristics; however, the new variety ‘W1’ differs in the following;1. Petals of the new variety are more rounded and overlapping than petals of this comparator.2. Sepal color of the new variety is green, while sepal color of this comparator is purple.

Plants of the new cultivar ‘W1’ are comparable to the commercial varietyPhiladelphus‘P1’, plant patent application number 18/118,353. The twoPhiladelphusvarieties are similar in most horticultural characteristics; however, the new variety ‘W1’ differs in the following;1. Petals of the new variety are more rounded and overlapping than petals of this comparator.2. Petals of ‘W1’ are more reflexed back than petals of ‘P1’.3. Petals of ‘W1’ are white, petals of ‘P1’ are white with pink.

DETAILED BOTANICAL DESCRIPTION

In the following description, color references are made to The Royal Horticultural Society Colour Chart 2015 except where general terms of ordinary dictionary significance are used. The following observations and measurements describe ‘W1’ plants grown outdoors in Waddinxveen, the Netherlands. The growing temperature ranged from approximately 18° C. to 27° C. during the day and from approximately 5° C. to 10° C. during the night. General light conditions are normal sunlight and numerical values represent averages of typical plant types.Botanical classification:Philadelphussp. ‘W1’.

PROPAGATION

PLANT

FOLIAGE

FLOWER

REPRODUCTIVE ORGANS

OTHER CHARACTERISTICS

Fruits and seeds: Not observed to date.Disease/pest resistance: Neither resistance nor susceptibility to normal diseases and pests ofPhiladelphusobserved.Temperature range: Winter hardy to −15° C.