Garden Lore

“Once it has a toehold, incongruity has a way of advancing systematically through the garden like quackgrass.”

Des Kennedy, Crazy About Gardening (1994)

A wonderful blue but don't trust this commelina in NZ

A wonderful blue but don’t trust this commelina in NZ

Garden Lore – weed plants

We bought a packet of seed of this pretty Commelina coelstris ‘Sleeping Beauty’ a few years ago and we have been working on eradicating it ever since. Mark decided it was dangerous as soon as he saw the seed set, even before we found that if you fail to remove all the tuberous roots, it can stage a comeback. It has such a pretty blue flower and we are fans of blue. Mind you, it is not as if it flowers in abundance like the common lobelias that seed down here and do no harm at all. I checked an American website and opinion was divided on the invasiveness of this plant but its ability to grow across a huge range of climatic zones, in every soil possible and in both sun and shade is a good indicator of weed potential in the hospitable conditions we have in this country. Pretty wildflowers in harsher climates can be an environmental curse here.

We haven’t complained to the seed company selling the commelina. Last time we mentioned to them about the weediness of a line they were selling (it was so-called strawberry spinach), the response we got was a dismissive: “Nobody else has had a problem with it”. The sub text to this might be: ‘we have no intention of stopping selling this plant and clearly you have no idea what you are talking about’. Since then, we have noticed others complaining about strawberry spinach. It took us years to eradicate it. It wasn’t even particularly appetising. Buy this, or the commelina at your peril. Campanulas are a better option for easy-care blue flowers.

First published in the Waikato Times and reprinted here with their permission.