A 29 June 2012 Calgary Herald article by Carole Dobson suggested that Calgary gardeners consider planting Philadelphus Mock Orange, instead of its much less hardy cousin but very popular, Hydrangea. Dobson recommended Philadelphus lewisii ‘Waterton’ which is native Alberta’s Waterton Lake region.

The Mock Orange rounded deciduous shrub is full of orange-scented white blossoms in June. The Mock Orange attracts butterflies and birds and is deer resistant. It grows in Zone 3.

It prefers full sunlight, and a well-drained soil. Its average height and width at maturity is 10′ – 12′, according to gardening expert David Beaulieu. In his 13 Sep 2022 article in The Spruce, Beaulieu describes different varieties of Mock Orange bushes as well as useful advice on their care and maintenance.

The City of Calgary recommends the Mock Orange as YardSmart and WaterWise. Once established, this hardy native plant, only needs to be watered during periods of drought.

Nurseries recommend the addition of a mycorrhizal inoculant—a root builder—at the time of transplanting bushes and trees. This Garden Gate Magazine 22 Dec 2023 article describes how to do that. It also provides lots of other useful content on mycorrhizal inoculants.

Pruning

According to a August 4, 2021 article by David Beaulieu published in The Spruce, “Mock orange shrubs bloom on the prior year’s growth” so we should “prune the shrubs immediately after they’re done blooming”.

Beaulieu says that we should

• Prune the growth on stems that have just finished blossoming where you can see outer-facing buds
• Prune off any dead, damaged, or poorly shaped branches.

Rejuvenating older, overgrown mature shrubs

Beaulieu says that as the shrub becomes overgrown over the years, he advises gardeners to “cut the oldest one-third of the branches down to ground level at the time of your annual pruning…After three years of such pruning, the shrub should look healthier. For severely overgrown shrubs, prune all the branches to the ground in the spring. You won’t enjoy blooms that year. But this rejuvenation pruning will soon have healthy new branches popping up from the shrub’s base.”

Parkdale Community Garden

The Mock Orange from my home garden was transplanted in 2015 to the Parkdale Community Garden to what is now called the Mock Orange perennial circle. This bed now includes many hard perennials such as delphineum, Karl Foerster decorative grass, red lilies, tall daylilies, purple sage, sticky cranesbill geranium, persian cornflower, a rose bush, and many ground covers including periwinkle.

The Mock orange in the the centre of our slightly raised Community Garden’s perennial circle, is in full bloom by mid-June. It has a sweet scent of orange blossoms.

This is a bed that has experienced irregular watering and the bush is very healthy.

Other useful resources for Calgary gardeners

Kath Smyth, who is a “certified horticulturist, and a 5th generation Albertan”, produced a useful list of her favourite shrubs and trees that is available on the City of Calgary’s YardSmart and WaterWise program in the form of a downloadable 4-page illustrated PDF file. On her list of shrubs that are best suited to Calgary, she included the Waterton Mock Orange – Philadelphus lewisii ‘Waterton’; along with Diabolo Ninebark – Physocarpus opulifolius ‘Monlo‘; Red Leaf Rose – Rosa glauca; Rose Glow’ Barberry – Berberis thunbergii ‘Rose Glow’; Ivory Halo Dogwood –Cornus alba ‘Bailhalo’; Dwarf Korean Lilac – Syringa meyeri ‘Palibin’; Goldflame Spirea – Spirea x bumalda ‘Goldflame’; Turkestan Burning Bush – Euonymus nana ‘Turkestanica’; Clavey’s Dwarf Honeysuckle – Lonicera x xylosteoides ‘Claveyi’; Saskatoon Berry – Amelanchier alnifolia; Goldfinger Potentilla – Potentilla fruticosa ‘Goldfinger’; Savin Juniper – Juniperus sabina; Nanking Cherry – Prunus tomentosa; Sem False Spirea – Sorbaria sorbifolia ‘Sem’; Bird’s Nest Spruce – Picea abies nidiformis; Calgary® Carpet Juniper – Juniperus sabina ‘Monna’; and Buffalo Juniper – Juniperus sabina ‘Buffalo’.

About the author

Maureen Flynn-Burhoe is not an expert and has no formal training in gardening. All content added here is based on personal experience and is informed by reliable sources cited inline.

I follow and highly recommend the City of Calgary’s YardSmart and WaterWise programs.

I have maintained a large perennial home garden since 2008 and have been active in the Parkdale Community Garden since 2016.

I highly recommend Western Canadian Garden Soil for compost, mulch, and garden soil.