Plants out of Place

Treated myself to a new book recently – The Wondrous World of Weeds by Pat Collins, a qualified medical herbalist who teaches widely in Australia. The book was published this year by New Holland.

Why did I buy it? Well, I have plenty of great plant and garden reference books on my shelf but the cover made me realise I have few books that deal with wild plants and not one that specifically addresses ‘weeds’ – and most of the plants featured are also to be found in New Zealand so it will be a help with identification.

Thanks to Julia Sich and her love of edible weeds I’ve already had my mind opened a little to the fact that weed ≠ useless. They are, as Pat says “a plant out of place” and for millennia traditional societies have known all about the nutritional and medicinal values of wild plants.

I guess we began losing the knowledge about the same time that farming became mechanised and then large-scale, and manufacturing (and its workforce) moved from ‘cottage industry’ to factories in urban centres. Weeds (or plants out of place) can ruin a valuable crop and there probably weren’t many salad greens to be found growing in the cobbles of Manchester.

I’ve just come in from pulling handfuls of newly sprouted Euphorbia peplus (milkweed) from the garden and am delighted to read in Weeds that the milky latex sap the stem exudes is “renowned for its use on suspect sunspots”. This 2011 article details the findings (good) of an Australian dermatological study.

My perennial patch of onion weed (Allium triquetrum) is shooting forth again too – no matter how much I extract bulbs or snap off flower heads I can’t seem to be rid of it. Pat Collins advises me eating the flowers and stems raw in salads and the bulb once the plant has died down. A sweet revenge if ever there was one! Listen to a 2009 RNZ broadcast about foraging for onion weed (12:34) or read this 2015 UK Permaculture article.

Prickly pear flowers in Wellington Botanic Gardens. Each will turn into a spine-coated fruit. Photo: Sandra Simpson

One weed we thankfully don’t have in New Zealand is prickly pear (Opuntia stricta) but it’s widespread in other parts of the world, including Australia where it was introduced in the 19th century for use as a hedge before “spreading at an alarming rate”. A Prickly Pear Board was tasked with ridding the country’s grazing land of this prickly menace, eventually bringing it to manageable levels with biological controls.

“In Mexico and other countries, it is used for diabetes,” Pat Collins writes. “I have been experimenting with this on diabetics with amazing results. You soak clean pads [sections of the cactus-like plant], scour with a fork, cover in water and bicarbonate of soda and drink the next day. However, the mixture is unpleasant, slimy and I had trouble getting people to take it.”

But another one I have plenty of – and coming through the fences – is Tradescantia fluminensis (wandering Jew, wandering willie). Guess what? The leaves are edible! Pat Collins uses thick mats of the stuff as a living mulch around fruit trees and says “it cuts down watering by 30%” and that the plant itself is more than 90% water.

“Easy to pull up but hard to eradicate as if you leave a small piece of root it will regrow.” And don’t I know it.

Recommended as a fun, informative read.