Riverside® Hybrids – Our vision


“Our vision is to supply growers with hardy and distinct polyploid hybrids. This ensures that the hybrids which we release are easy to care for, vigorous, hardy, free-flowering and spectacular.”

Myles S Irvine

Myles S Irvine

Riverside® Hybrids Passiflora breeder

Myles Irvine has been growing Passiflora for over 30 years and has released a number of hybrids over that time. With Passiflora particularly creating new hybrids is a war of attrition, but the satisfaction of the successes is always worth the wait. The best of these have been selected for worldwide distribution as the Riverside® hybrids.

Myles created the site Passiflora Online back in the year 2000, started the Passiflora Online Facebook Group in 2007 and is editor of the free to download Passiflora Online Journal.


August 2017

Plantarium Trade Fair. The Riverside® Hybrids Passiflora ‘Damsel’s DelightPassiflora ‘Snow Queen’ have been added to the prizewinning FleuraTerraza range by Dutch climber specialists Van der Starre. FleuraTerrazza includes a range of climbers selected to ensure they will bloom in spring, summer and after summer.

June 2017

Horticultural Trade Association National Plant Show. Riverside® Hybrid Passiflora ‘Snow Queen’ wins HTA National Plant Show 2017 Shrubs and Climbers Gold Award and best in category – Presented by Newy PPL

‘Pure Passion’ Plant Profile

on Myles Irvine by Philip Clayton
The Garden (RHS) Volume 135 Part 9 September 2010
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Investigation of Passiflora hybrids using flow cytometry

L.A. King and M.S. Irvine
Passiflora (2010), 20(1):pp. 5-11
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‘Breeding hardy Passiflora by Myles Irvine

The Plantsman (RHS) New Series Volume 9 Part 3 September 2010
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Passiflora Online Journal ISSN 2046-8180.

Ten issues to date,  articles by academics and enthusiasts worldwide. Fabulous photo galleries.
Download issues here

The history of Passion flower hybrids

The earliest known Passion flower hybrids were created in the early 19th century. Since that time hundreds of hybrids of these fabulous flowers have been created, of which sadly many have been lost over the years. Few are hardy however and fewer still are polyploid, Polyploidy means having more than the usual two sets of paired chromosomes. It is one of Nature’s ways of speedily adapting to environmental change. Our advanced breeding techniques are now starting to produce polyploid Passion flowers with three or even four sets of chromosomes per cell. This gives easy to care for plants with increased vigour and larger, stronger flowers which often stay open for several days.

Riverside® Hybrids have the following advantages for both nurseries and home gardeners:-

Free flowering

All the selected Riverside® hybrids are free-flowering, producing flowers at every node over a period of many months, often May-November.


The solidity of the striking polyploid flowers lends itself to more intense colours that stand out strongly against other plants around them.

Size matters

All Riverside® Hybrids compare favourably with Passiflora caerulea, producing bigger, stronger longer lasting flowers.


Hardiness is approximate but these should survive occasional dips down to -8°C, 18°F or USDA zone 8b.