Recently I had a visitor ask me about how I managed weeds if I didn’t use chemicals. Since we purchased our property 6 years ago, I have been passionate about demonstrating how it is possible to control weeds without chemicals and I figure if we can do it on three acres, it is possible to manage in a suburban garden.
There are a number of ways we do this.
Sadly, in our quick fix world, ‘hand weeding’ is often overlooked in an endeavour to be hi-tech and save time with the latest and greatest cure-all spray. Many gardeners ignore the seeding weeds and choose to ‘give them a squirt’ with herbicide after the horse has already bolted. Many weeds are easy to pull out if the soil is moist and friable. Hand weed where possible, especially where the weeds are growing close to existing plants. Digging out weeds with a fork or other gardening implement can also be helpful although be aware that excessive cultivation damages the soil and has the potential to damage roots of garden plants that we want to keep. Chipping cuts the weeds off just below ground level using a sharp implement such as a spade or hoe and this results in little root disturbance. Recently I weeded the edge of my driveway corridor where some paddock grasses had seeded in the gutter. After a recent shower of rain when the ground was softened, I was able to pull out a wheelbarrow of small weeds assisted by a hand hoe in a relatively short time. A good practise is always to pull out a few weeds as you walk around enjoying your garden!
Mowing is ideal for those with larger properties which have areas of grass that is mowed to form a sort of lawn. Whipper snippering works the same way and at Sophie’s Patch we also bale our paddock to give me hay bales. Our flock of geese is very effective at grazing our orchard for most of the year. This falls in a bit of a hole in spring when the girls want to lay eggs and nest. I should remove the eggs and not let them sit on them as while they do, the grass grows tall very quickly. As geese prefer short grass to long, I then actually need to whipper snipper the orchard once to get them to keep it low again!?
Sheet mulching – using non-glossy cardboard or newspaper and covering it with a generous layer of mulch. In time the cardboard and paper will break down. That is why you will see newspaper and cardboard peeking out from under the mulch, especially where our chooks and ducks have been scratching. We also use carpet covered in mulch in certain areas as a temporary method of making the weeds manageable. Most carpets contain synthetic fibres which will not break down so they will need to be removed in time.
You can read more about sheet mulching in the ‘Sheet mulching’ post.
We solarise the soil by covering it with black plastic in summer to kill existing weeds and weed seeds. Although the earthworm and soil microbes do not like being in the area being solarised, they will return when the plastic is removed. Ideally you need to make sure that the weeds are mowed low and the ground has some moisture in it. Leave the plastic down for a month to six weeks over summer and utilise the scorching summer temperatures (the hotter the better) to kill the existing weeds… and kill any weed seeds.
Ideally you should secure all the edges either by digging them into the ground or weighting them down so that no light can get in. I use the black plastic salvaged from under my Royal Adelaide Show feature gardens and the hardest thing is finding enough bricks, logs and anything else we can find to hold it in place. Try to time lifting the plastic for a scorching day, as any weed growth that remains will be pale or white, and then get burnt when exposed to the sun. For more detailed information on solarisation read Tim Marshalls piece in his growing organic website.
Finally it should also be said that prevention is the best form of weed control. Take positive steps to stop prevent weeds from spreading around the garden, by removing them before they seed and eliminating existing weeds before you plant a garden bed. Finally, after removing weeds, it is vital that you apply an even layer of mulch to prevent further weed seed germination. It is an absolute waste of time to weed, and not mulch afterwards. Finally dense planting means there is no room for the weeds to grow and this is a great way eliminating many annuals weeds.
Is it effective? This whole property was simply a cow paddock three years ago and so we have managed to control most weeds very effectively. I will admit though that there is one weed we do struggle with and that is bindweed. It is present in a small band on this edge of the property. It will resist all of the above non-chemical control measures however I know that it is also almost impossible to kill even with chemicals. So what do we do? Learn to live with it! Weed it out where we can and allow the plants to become strong enough that I can’t see it.
There are also a number of organic herbicides on the market which can be used and recently I have been impressed with Slasher which is based on Pelargonic acid. It burns the weeds and the results can be seen within an hour. This year I plan to use this to deal with the weeds that come up in the cracks in our pavers and also the weeds which grow on the edge of the driveway. Previously I have managed these weeds by hand weeding and hoeing.