ENGLISHFive new varieties receive ISU-Awards
Every second year, the International Perennial Society (ISU) organises the Summer Days. This year the Summer Days took place in Lund, Sweden, from 16 August until 20 August. 60 ISU members from Europa and the USA gathered together for a five day program with trials, lectures, excursions to nurseries, public green spaces and gardens. During the Summer Days, the ISU Trials Committee judges new perennial varieties, sent in by various growers from around the world. The best new perennials receive the prestigious ISU-Awards.
The number of Awards granted by the ISU Trials Committee is determined by the number of entries. A maximum of 10% of the entries may receive an Award (with a maximum of 10 Awards). Depending on the number of judges present, a minimum number of votes is also required to be eligible for an Award. In the 2026 trials, there were 53 entries, which meant a maximum of five Awards could be granted.
The five highest-rated cultivars all achieved the required minimum number of votes, so the Trials Committee awarded five Awards.
In addition, participants at the Summer Days can also vote, after which one cultivar is awarded the Peoples’ Choice ISU-Award.
Of the 53 entries for the trials, 49 could be evaluated. The growers and breeders applied for the trials in autumn 2024 and spring 2025. The applicants then sent five plants of each entry to Karin Svensson of SLU Alnarp, who took care of the plants for over 1.5 years. Svensson showed the development of the plants in a presentation to the ISU Trials Committee, who then discussed all plants. The committee consists of members from 12 countries and is chaired by Ronald Houtman (Netherlands). After the meeting the Committee evaluated the plants in the trials field of SLU Alnarp. The following five new perennials received an ISU-Award:
Agastache ‘Agapk’ (BEELICIOUS PINK) (Kopie)
Applicant: Plantipp BV, IJsselstein, Netherlands
Vigorous perennial that will grow to about 1.25 m tall and wide. The mid-green foliage is pleasantly fragrant. From midsummer into early September dense racemes with masses of light pink flowers open. The dark purple calyxes contrast very well with the lighter flowers. After the flowers have dropped, the remaining calyxes keep on giving this plant ornamental value. The flowers attract lots of bees, hoverflies, butterflies and other pollinating insects. BEELICIOUS PINK is best used as a specimen plant or in large perennial borders. Grows best in full sun in any well-drained soil types, not too wet. Besides the ISU-Award granted by the ISU Trials Committee, BEELICIOUS PINK also received the Peoples’ Choice ISU-Award.
Aster ×amethystinus 'JS Trendwende' (Kopie)
Applicant: Spruyt Select CommV - Jan Spruyt, Buggenhout, Belgium
Aster ×amethystinus is a hybrid between Aster novae-angliae and A. ericoides. ‘JS Trendwende’ is a very vigorous, late-flowering Aster. In one year, a small plant can reach a height of about 30 cm and a diameter of over 60 cm. The small leaves give it a fine texture. The flowers open from mid-September into October. They are lilac-pink with dark yellow centers. ‘JS Trendwende’ is an impressive plant, highly effective for mass planting in large areas. It thrives best in full sun and semi-shade in any well-drained soil.
×Oredenia 'Fusion of Fire' (Kopie)
Applicant: Johan Nilson, Göteborg Botanical Garden, Göteborg, Sweden
×Oredenia is and intergeneric hybrid between Oresitrophe and Mukdenia. It combines the best properties of both parents, with a healthy growth to 40 cm high and 60 cm wide. The lush green leaves are broad ovate with attractive serrate margins. In autumn they colour deep red tot purple-red. The pinkish white, star-like flowers open in spring. ‘Fusion of Fire’ is more vigorous and more floriferous than Mukdenia, the best-known of the two parents. It is best grown in well-drained, moist soil in a semi-shaded location of in filtered sunlight.
Sesleria heufleriana 'Overdam Blue' (NORĐIC) (Kopie)
Applicant: Future Plants Licentie BV, Hillegom, Netherlands
An evergreen ornamental grass that will grow to about 40 cm high and 50 cm in diameter. It has a denser growth than the species S. heufleriana. The leaves are slightly broader too, adding to the density of the plant. They are dark green with a conspicuous greyish layer, creating the bluish impression. NORĐIC flowers in late spring with almost black spikes of flowers, holding cream-coloured anthers. Excellent for use in group plantings, it grows in any well-drained soil, in full sun or light shade.
Sorghastrum nutans 'JS Michelito' (Kopie)
Applicant: Spruyt Select CommV - Jan Spruyt, Buggenhout, Belgium
Impressive tall grass with a sturdy habit that will easily grow to over 1.5 m high when in full bloom. The leaves are attractive greyish blue and colour pinkish-orange to red in autumn. The even more impressive flower panicles appear from midsummer to late summer. They are warm red-brown with light yellow anthers. The foliage and flower colours go extremely well with each other. Excellent for use in small groups or as a specimen plant in mixed borders and prairie gardens. Like other Sorghastrum nutans, ‘JS Michelito’ is drought tolerant, and grows in any well-drained soil, preferably in full sun.