A new and distinct cultivar of Helleborus plant named ‘BLT04’, characterized by its compact, upright and mounded plant habit; strong and vigorous growth habit; leaflets with distinctive venation; freely flowering habit; single pink-colored flowers; and good garden performance.

BACKGROUND OF THE INVENTION

The present invention relates to a new and distinct cultivar ofHelleborusplant, botanically known asHelleborus niger×Helleborus sternii,and hereinafter referred to by the name ‘BLT04’.

The newHelleborusis a product of a planned breeding program in Hampshire, United Kingdom. The objective of the breeding program was to create new frost-tolerantHelleboruscultivars with unique and attractive flower coloration.

The newHelleborusplant originated from a cross-pollination in Hampshire, United Kingdom in 2000, ofHelleborus niger‘Louis Cobbet’, not patented, as the female, or seed, parent with a proprietary selection ofHelleborus sternii, not patented, as the male, or pollen, parent. The newHelleborusplant was discovered and selected by the Inventor as a single flowering plant from within the progeny of the stated cross-pollination grown in a controlled environment in Hampshire, United Kingdom in 2000.

Asexual reproduction of the newHelleborusplant by tissue culture in a controlled environment in The Netherlands since 2000, has shown that the unique features of this newHelleborusplant are stable and reproduced true to type in successive generations.

SUMMARY OF THE INVENTION

The following traits have been repeatedly observed and are determined to be the unique characteristics of ‘BLT04’. These characteristics in combination distinguish ‘BLT04’ as a new and distinct cultivar ofHelleborus:1. Compact, upright and mounded plant habit.2. Strong and vigorous growth habit.3. Leaflets with distinctive venation.4. Freely flowering habit.5. Single pink-colored flowers.6. Good garden performance.

Plants of the newHelleboruscan be compared to plants of the male parent selection. Plants of the newHelleborusare more freely flowering than plants of the male parent selection.

Plants of the newHelleboruscan be compared to plants of the female parent, ‘Louis Cobbet’. Plants of the newHelleborushave larger flowers than plants of ‘Louis Cobbet’.

Plants of the newHelleboruscan be compared to plants ofHelleborus niger×Helleborus sternii‘HGC Silvermoon’, disclosed in U.S. Plant Pat. No. 15,639. Plants of the newHelleborusdiffer primarily from plants of ‘HGC Silvermoon’ in the following characteristics:1. Plants of the newHelleborushave larger and lighter-colored leaves than plants of ‘HGC Silvermoon’.2. Plants of the newHelleborusare more freely flowering than plants of ‘HGC Silvermoon’.3. Plants of the newHelleborusand ‘HGC Silvermoon’ differ in flower color as plants of ‘HGC Silvermoon’ have white to light green-colored flowers.

DETAILED BOTANICAL DESCRIPTION

The aforementioned photograph and following observations, measurements and values describe plants grown in Aalsmeer, The Netherlands in containers during the winter in a glass-covered greenhouse and under conditions which closely approximate commercialHelleborusproduction. During the production of the plants, day temperatures ranged from 14° C. to 16° C. and night temperatures averaged 10° C. Plants had been growing for one year when the photograph and the description were taken. In the following description, color references are made to The Royal Horticultural Society Colour Chart, 1995 Edition, except where general terms of ordinary dictionary significance are used.Botanical classification:Helleborus niger×Helleborus sternii‘BLT04’.Parentage:Female, or seed, parent.—Helleborus niger‘Louis Cobbet’, not patented.Male, or pollen, parent.—Proprietary selection ofHelleborus stemii, not patented.Propagation: