Invasive flowers a headache for gardeners, says Saskatoon horticulturist

Flowers with aggressive root systems or intense seed production outcompete other plants, eventually taking over an entire yard or garden, if not controlled.

Flowers can take over lawns and gardens, killing off other plants

This perennial flower will invade and take over a garden if left uncontrolled says horticulturist Grant Wood. (CBC/Stefani Langenegger)

They may be pretty to look at and easy to grow, but be careful what flowers you plant. 

Edmonton has declared war on  the creeping bellflower, placing it on its "most wanted" noxious weeds list. And although Saskatoon city officials haven't followed suit, horticulturist Grant Wood said gardeners need to be vigilant.

You're not going to eradicate in one year, even if you are using herbicides.- Grant Wood, horticulturist- Grant Wood, horticulturist

"They will spread, they will take over, they will outcompete the other plants," he said.

Wood said flowers like the creeping bellfower have a very aggressive root system. Others like the Himalayan balsam, more commonly known as the poor man's orchid, have huge seed production.

Wood said the most effective way of controlling the plants is by digging and destroying.

"You're not going to eradicate in one year, even if you are using herbicides," he said.

Top 10 Invasive Plants in Saskatchewan

1. Goutweed. 
Aegopodium podagraria. (Island Nature Trust)

2. Creeping bellflower. 
Campanula rapunculoides. (CBC)

3. Shasta daisy.
Not all cultivars are aggressive. (Wikipedia)

4. Achillea.
Achillea. (Wikipedia)

5. Common tansy.
Tanacetum vulgare. (Wikipedia)

6. Leafy spurge.
Euphorbia esula. (US Fish & Wildlife Service)

7. Dame's rocket.
Hesperis matronalis. (Wikipedia)

8. Purple loosestrife.
Lythrum salicaria. (Jim Lavrakas/Associated Press)
9. Himalayan balsam.
Impatiens glandulifera. (Beth Hoar/Green Thumb Photography)
10. Scentless chamomile.
Matricaria maritime. (CBC)

With files from CBC's Saskatoon Morning