…sweet flowers are slow and weeds make haste

“…sweet flowers are slow and weeds make haste.” William Shakespeare, Richard III

They say there’s no such thing as a weed, it’s just a plant in the wrong place! Whatever they are, weeds or misplaced flowers, vines won’t benefit from competition for nutrients and moisture in the hot and dry summers of the Robertson valley. It’s also necessary to keep weeds in check so there is a proper circulation of air thereby reducing the risk of disease and habitats for pests, and to improve labour and harvest efficiency.

Traditionally farmers have always battled against invasive plants. Back in the old days they would use a horse drawn plough to go down the vineyard rows and then dig, by hand, between each vine (called a bankie). But one horse power isn’t a great deal of power and the plough simply couldn’t cut through the canes that had been thrown on the ground post pruning, nor could it get through larger weeds. And then even if it could did get through, everything had to be carted out by hand. Stock animals, particularly sheep, were also used to keep the weeds in check. In Europe they sped the process up by putting the canes, dug up weeds etc. into a wheel barrow and setting it alight – instant nutrients for the vines and it kept people warm!

Post World War II tractors were used to pull a disk plough along the vineyards. This worked better since a tractor has substantially more power than ‘one horse ’ and the disk plough could cut up the canes dropped in pruning. But the vibrations and the weight of the machine caused a shake down in the soil – small particles descended and larger particles were thrown up;  a plough sole forms through which water and plant roots find it difficult to penetrate. Farmers also tried cutting down weeds and leaving the roots to rot in the soil.

Modern farmers use weed killers. Pre-emergent weed killers are, as the name suggests, used to prevent weeds appearing while post-emergent weed killers help tackle a weed problem once it’s arrived. Pre-emergent weed killers are cheap and effective. But (and this is a big but), with repeated used they can leave the soil sterile and water penetration can be deteriorated. At Excelsior we never use this kind of weed killer on our vines. We’re more ‘live and let live’ with the weeds – they’re high in cellulose which provides both micro and macro organisms with food and contributes to overall healthy soil. In fact we encourage weeds to contribute to a balanced eco system. Members of the brassica family are welcome along with clover, grasses and wild oats and barley. Canadian horse thistle is a problem – it dominates given half a chance and is resistant to weed killer.

When we need to control the weeds we take action by mowing them down – 2-3 times annually.  We also spray post-emergent weed killer when necessary; we use is sparingly and time it carefully so that the plant material is well developed and has an established root system. The plant material is then left on the top of the soil to protect it from the sun and to return the nutrients.

p.s. Do you know where ‘horse power’ comes from? Leave a comment if you do!

Sources and further reading:

Weed Control in New & Established Vineyards

Wikipedia – Weed

SA Weed Science Society

Plough Sole as the result of Agricultural Land Use

Alien Invasive Plants in South Africa

Cheaper vineyard weed control never -ending quest

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