When the green fades, the red and orange get to shine

Written by Ilona Biro, Volunteer

It’s October, and in the Northern Hemisphere, Mother Nature has taken out her paint box and created a rich palette of reds, golds and copper in a stunning last show of colour. Of course, the scientific reason for this brilliant northern spectacle is a bit more down to earth. It has to do with the shorter days and longer nights of autumn, and the slowdown in food production, which is the main activity of leaves throughout spring and summer. This food-making process takes place in leaf cells containing chlorophyll, which gives leaves their green colour. This extraordinary chemical absorbs from sunlight the energy that is used in transforming carbon dioxide and water to carbohydrates, such as sugars and starch.

Along with the green pigment are yellow to orange pigments, carotenes and xanthophyll which, for example, give the orange colour to a carrot. Most of the year, these colours are masked by great amounts of green pigment. But in the fall, food production comes to a halt, the chlorophyll breaks down, and the green colour disappears, allowing the red and orange pigments to shine.

This glorious phenomenon is ours to enjoy, so get out and try to see the radiant colours when they’re at their peak: any time from now to Oct 15. Of course, another way to experience this display without travelling too far, is by planting fall-blooming flowers, and colourful shrubs or trees in your own garden.

Here are some of the best for Ontario’s climate:

Shrubs

Sumac Rhus orange/red

Blueberry Vaccinium orange

Dogwood Cornus reds and orange

Wayfaring Tree Viburnum lantana purple/bronze

Burning Bush (Euonymus alatus)Burning Bush (Euonymus alatus) fuchsia

Fall Flowering Shrubs

Common Name Latin Name Colour

Bluebeard Caryopteris blue

Butterfly Bush Buddleia purple, blue, pink, white

PeeGee

Hydrangea Hydrangea white/pink

Witch Hazel Hamamelis yellow

Trees

Mountain Ash Sorbus orange, red, yellow

Ginkgo Ginkgo bilobam yellow

Larch Larix yellow

Sugar Maple Acer saccharum orange and red

Red Maple Acer rubrum red

Perennials

False Dragonhead (Obedient Plant). Physostegia spp. white, pink, purple

Balloon Flower Platycodon spp. blue, white

Black-eyed Susan Rudbeckia spp. yellow

Sedum Autumn Joy. Sedum spectabile. pink, mauve

Monkshood Aconitum blue

Japanese Anemone Anemone japonica pink/white

Mugwort Artemisia lactiflora white

Italian Aster Aster amellus blue, purple

New England Aster A. novae-angliaepurple, pink, white

New York Aster. A. novi-belgii violet

Coreopsis yellow (flowering since June, will still be flowering in Sept.)

Purple Coneflower Echinacea purpurea purple

Globe Thistle. Echinops. blue

Cardinal Flower. Lobelia cardinalis scarlet

Blue Cardinal Fl. L. siphilitica blue

Catmint Nepeta spp. blue

Giant Sundrop. Oenothera missourensis. yellow

Phlox Phlox paniculata. pink, white (flowering since July)