Crocosmia is popular with hummingbirds

Yes, even beautiful flowers can become weeds, unless the gardener pays attention to its offspring. Hummingbirds go for crocosmia, but the flower can get out of hand if not deadheaded or its prolific corms kept in check.

Some weeds are in the eye of the beholder and others just plain obnoxious.

Casey Leigh explained about our state noxious weed list and how to get more information on them in her Jan. 11 column. The following week Bonnie Orr warned of a new, insidious aquatic weed, flowering rush, that’s been found in the Columbia River near Orondo and Turtle Rock. Last week, Connie Mehmel wrote about fast-growing Siberian elm, a problem tree.

I’m concluding our four-week weed wind-up by writing about how weeds become weeds — some by neglect and some by happenstance.

What makes a weed a weed?

It can multiply by various insidious methods. Deep, invasive roots of bindweed (a morning glory relative) and horsetail are too deep to dig or even penetrate with effective sprays. In addition, small pieces can root and take hold — alas, a new plant. Gardeners seem to rate bindweed as their No. 1 nemesis.

Wind and gentle breezes carry a multitude of seeds — such as the attractive little white parachutes of dandelion seeds or the coin-sized parchment circles of Siberian elm. These problems get innocently carried into all our yards, orchards and pastures, ready to take hold in little crevices. Many weed seeds are viable for 50 years or more; another obnoxious attribute.

Another clever way of dispersing seeds is the infamous puncture vine. Sharp little needles grow attached to seeds, so when we walk or drive on them, they cling to our shoes and tires, hitchhiking to a new location. Puncturevine is a Class C weed here, requiring control measures.

Then, there are desirable plants that, if allowed, become weeds. Those pretty flowers attract our eye — that is until they reseed with a vengeance and threaten to overcome our flower beds.

There are ways to keep these in check; either deadheading or digging may suffice, depending on the plant. Some asters, bamboo, ivy Mexican feather grass and sweet woodruff are in this category. Mint can be an underground monster, so I advise limiting it to a pot. Being aware these need to be limited by either digging or deadheading to make them acceptable.

Providing fertile soil and water, several plants can become your enemy. In drier, less lush conditions, they may remain respectable.

Crocosmia is another potential friend and foe. They produce arching stems with a lineup of pretty tube-shaped flowers — sure to attract hummingbirds. As the flowers shrivel and dry, they eventually fall to the ground and those innocent little corms (bulb-like seeds) take hold and before long shoulder out nearby plants in good garden conditions.

After not paying attention to their devious ways one year, I paid the price of finding a whole nest of emerging crocosmia. I dug up most, just keeping a few to enjoy. This year I’ll be vigilant in my deadheading, not letting them become weeds.

Strolling through your garden is pleasant exercise and a chance to observe potential troublemakers, saving time and frustration down the road.

A WSU Master Gardeners of Chelan County column appears weekly in The Wenatchee World. Mary Fran McClure is one of four columnists featured.