• AGM plants

    AGM plants have been through a rigorous trial and assessment programme. They are:

    • Excellent for ordinary use in appropriate conditions
    • Available to buy
    • Of good constitution
    • Essentially stable in form & colour
    • Reasonably resistant to pests & diseases

New AGMs for New Guinea Group

In 2014 we held an AGM trial of Impatiens New Guinea Group hybrids at RHS Garden Wisley

The container-grown trial of Impatiens New Guinea Group, an exotic cousin of the busy lizzieThe breeding of New Guinea Group hybrids (Impatiens) has in recent years been very intense as breeders have been trying to introduce new cultivars suitable for gardens and patios.

One of the first marketable developments was in 2006 when a Japanese company (Sakata) introduced a cultivar sold in the market under the name SunPatiens Magenta. This was very vigorous and it was introduced as a sun-loving plant for the garden. The market was aimed at the US and southern Europe, but trials in northern Europe found that the product performance in the garden was very acceptable.

One problem the introduction faced was getting people to see this was not ‘just another impatiens’ because Impatiens walleriana (busy lizzies - which had been the top bedding plant in market share and revenue for several seasons) had suffered the devastating effect of downy mildew in the UK and British growers have seen a sudden and dramatic drop in sales.

The open-ground trial of Impatiens New Guinea GroupOur trial of Impatiens New Guinea Group hybrids was composed of 100 cultivars from seven of the world’s major breeders and they were planted in the border and in containers with a diameter of 40cm (16 in). The more vigorous cultivars such as those from the SunPatiens and Sun Harmony Series were planted one in a container.

The trial revealed a lot of important information, not only for the grower but also for the landscape designer and for the consumer. The most important point which must be made crystal clear to the consumer is that the plants are ‘sun loving' to a degree: but partial shade and irrigation in the early morning or evening  is preferable, especially during the establishment period and also in periods of hot weather.

Judging the trial of Impatiens New Guinea Group at RHS Garden WisleyOur trial gave Award of Garden Merit (AGM) recognition to ten cultivars, nine of which are cutting-raised, the tenth of which was seed-raised.

In addition to the AGM judging we asked visitors to Wisley to vote for their favourite cultivar grown in a pot or in the border soil. In the containers the visitors and the judges agreed and the RHS People’s Choice also received an AGM.

In the border soil the visitors' favourite did not receive an AGM as the cultivar did not quite reach the full criteria in the RHS Forum's deliberations. The winners were:

People's Choice winners, Impatiens New Guinea Group hybrids:

For pots - SunPatiens Spreading Variegated Salmon
For borders  - Sun Harmony Compact Lavender


The AGM was awarded to the following cultivars:

Magnum Pink
Magnum Wild Salmon
Sun Harmony Salmon
Sun Harmony Deep Orange
SunPatiens Compact Blush Pink
SunPatiens Compact Orange
SunPatiens Compact Electric Orange
SunPatiens Spreading Variegated White
SunPatiens Spreading Variegated Salmon
Divine Violet

**PLEASE NOTE** Supplier marketing names are used in the lists of cultivars above.

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