In moments of laziness, I can be prone to the “scroll.” The feeds are primarily populated with stories and photos containing baseball, plants, friends’ kids or camping trucks/vans I could never afford.
A couple of weeks ago, a friend posted a photo of rabbitbrush, which in most years I love, but this year it seems to be firing up my allergies (in September!), and titled it “The start of yellow season.” I love that – the attribution of colors to a season, and she was so right. Shortly thereafter, Beth and I drove back down from a camping trip outside Rico, where we witnessed a weekend of yellow.
Aspens were starting to turn (and now they are close to peak color), and cottonwoods along the Dolores River showed their hints of change with the colder air settling along their path. We seem to be at the peak of the colors this first week in October, and as temperatures start dropping, so will the colors.
Environmental conditions, such as temperature, sunlight and soil moisture – can influence the quality of the fall foliage display. Fall colors – yellows, oranges, reds and purples – are revealed when the plant stops producing chlorophyll. As the chlorophyll (green color) disappears, pigments like xanthophyll (yellow), carotenoids (orange) and anthocyanin (reds and purples, which are actually manufactured from sugars trapped in leaf) are seen.
Cool temperatures, particularly at night, coupled with abundant sunlight, promote the formation of more anthocyanin. A hard freeze can destroy the mechanisms for manufacturing anthocyanin, so an early freeze frequently equates to an early end to colorful foliage. If the plant incurs drought stress during the growing season, it can sometimes cause leaves to drop before they have a chance to develop fall coloration.
The rabbitbrush was overwhelming the fences, open spaces and highway shoulders as we drove into the Mancos Valley. If you let it, rabbitbrush can get a little leggy, and if it is a good year for flowers, then the weight can pull the stems and branches down, making for a bit of an unruly appearance. In the landscape, you can always cut the plant back to about 1 foot in the early spring to keep it dense.
Then there were the sunflowers (it was the year of the sunflowers!). They can be aggressive, and some might even call them weedy. They can drive me a bit crazy in the garden, as they seem to pop up where you don’t always want them, and once they are they are there, it’s a yearly chore to get rid of them. However, it is hard to complain about a flower that can produce 20 or more heads on a single plant with little to no supplemental water. If you are nervous that all those seeds will produce all sorts of seedlings next year, then cut off the majority of the spent flower heads.
Soon enough, our landscape will take on the colors of winter, with the grays and browns finding their spots in the season of rest. Our hope is that a blanket of white will cover the landscape until spring, when the pinks and purples begin to stretch their legs.
Every season seems to have its colors, and every color sure feels like it belongs.
Darrin Parmenter is the director and horticulture agent of the La Plata County Extension Office. Reach him at firstname.lastname@example.org or 382-6464.