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Allan designs and plants flowering gardens in Montreal, Zone 5 [USDA Zone 4] .

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Consultation and coaching for do-it-yourselfers is provided. Occasional emailed questions are welcome and answered free of charge. Oui, je parle francais.

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Entries in late summer flowers (1)


Late Blooming Perennials

Some of my garden blogging friends who live in hot growing zones, report that their perennial flowers are spent by July due to the brutal heat of summer. I have had a different challenge. Historically, July was the month when I would leave town for vacation. Planning a late summer garden did not seem to be that important if there was no one at home to appreciate or tend to it. However, upon my return in August, I would be greeted by desolate flowerbeds and that was disappointing. This depressing situation became my inspiration to plan a colorful garden for late summer.

August in Canadian Zone 5 or US Zone 4 can be temperate. The days are usually hot and evenings are comfortable, sometimes cool. Flowers bloom nicely throughout the month; many will even flourish in September. With some planning, gardeners in this growing zone can have very colorful and interesting flowerbeds to finish off the season. Here are some of the perennials that I grow in August and September. I am certain that there are more than I have listed here. These are the old faithfuls that have worked for me.

Blue flowers for Late Summer:- Agastache, Campanula Samantha, Campanula porscharskyana, Campanula portenschlagiana, Clematis, Geranium Rozanne, Nepeta, Perovskia, Phlox paniculata , Platycodon, Scabiosa, Salvia, Verbena hastate, Veronica.

Pink flowers for Late Summer:- Aster Alma Potchke, Astilbe chinensis pumila, Astilbe taqueta superba, Clematis, Chrysanthemum  rubelum X Clara Curtis, Chelone oblique, Dianthus Deltoids and gratianopolitanis, Eupatorium, Geranium Sweet Heidi, Geranium Orkney Cherry, Geranium Max Frei, Phliox paniculata, Vernonia.

Hot Colored flowers for Late Summer:- Coreopsis, Echinacea, Gaillardia, Helenium, late blooming Hemerocallis, Knautia, Kniphofia, Papaver nudicale, Phlox paniculata, Sedum.

Flowering Shrubs for late summer:- Rainbow Knock Out Rose, Knock Out Rose, Rose Carefree Wonder, Rose Bonica, Hydrangea.