The Exton Gardener

One thing can be said about La Niña- she’s promoted some lush plant growth! Not all of this is welcome though.
The weeds...

My garden was once part of the farm and being rich arable basalt soil, the seed bank of weeds has built up in the soil.

A friend from Britain once exclaimed, “Look at all the wildflowers!” They may have been wildflowers in Britain but they are not our native plants and are weeds and not welcome here.

Years ago I purchased a copy of the Ag Department’s Tasmanian Weed Handbook and I felt I had every weed in the book except for Saffron Thistle and Nodding Thistle, an exaggeration perhaps, but I certainly recognise most of the illustrations.

I’ve been able to deal with most over the years with mulch and an occasional dab of weedicide when it became too overwhelming but there are three particular weeds I struggle with and I target them mercilessly.

The first I identified from the weed handbook as the creeping oxalis, Oxalis corniculata. Unlike other oxalis, it does not have underground bulbils but grows from a single tap root and then ground hugging rooting stems.

The leaves are a purplish green and there is a small yellow flower.

Like most legumes it has explosive seeds and it has a tendency to seed itself into the middle of choice plants and smothering them with its insidious growth.

Hand weeding seems to be the only way. If you can find the tap root you can remove most of the plant successfully. 

My second weed was not in the weed handbook. We sent a sample we first found in the paddock to the Mount Pleasant laboratories for identification.

A very British voice on the phone informed me that it was “Car-dam-in-ee pratensis”, otherwise known as Flick weed.

I have since found out that is Cardamine hirsuta though I don’t know what is hairy about it! It has of course spread widely since then.

Plant centres are rife with it and any waste corner has admirable specimens.

The trouble with it is it’s hard to spot unless it’s in flower and one missed plant will produce a forest of them in a month or two.

Vigilance and hand weeding seems to be the only solution. For me it is a work in progress!

Some years ago a new plant appeared in my garden. I had no idea what it was and it wasn’t in the book. I wondered if it was a native plant and let it grow a little before becoming wary and removing it.

Too late! It has since appeared every year in paths and garden beds. It appeared between the paving and when I started to pull it out it left a heap of seeds like dust.

The only way to destroy them was with a blow torch! I noticed the same weed in footpaths and car parks in Thailand and Japan but it is often very hard to see.

Google has now informed me that this little intruder is Euphorbia prostratus! It is native to the Caribbean but has spread worldwide.

Its common name is sandmat and an extract is apparently used to treat haemorrhoids! I suspect my initial plant came in a load of white gravel.

A friend said that he controls young plants with a spot spray of glyphosate, otherwise it’s a lot of hand weeding, or the blow torch.

But in spite of the weeds, the flowers are blooming.

The irises, the lupins, the ixias... and the roses! Enjoy spring and early summer - we deserve it after our wet and windy year.