Are you thinking of beginning the preparation process for a new native lawn or pasture?
Now is the time to start preparing a site for native grasses to be ready for the first autumn rains. The most important step in this process is tackling the weed problem. To change from an introduced pasture or lawn to native grasses without adequate weed control can exponentially increase your time spent on weed management in the long run.
Firstly ask yourself these questions:
– What is growing there now?
– What has been growing there in the past?
– What seeds may be in the soil?
– What is the herbicide/fertiliser history, if any?
If your land is dominated by weeds, it is likely that there is a heavy seed load in the soil. The weed removal process may therefore need to be repeated several times.
Secondly are you entering a dry or wet summer?
Depending on your Australian location, summer may be a period when weeds either grow or die. It depends on the weed species you have in your area. If your weeds are drying off, controlled burning may be a suitable weed removal option if burning off is allowed. If the summer is wet, manual weeding or herbicide use may be appropriate.
So what options do you have?
1) Hand or mechanical weeding. If your area is small enough to manage by hand you can avoid using chemicals or weed mats. Remove all the weeds either by hand or by using a tiller to turn over and/or aerate the soil. You can then rake away any weeds left on the surface.
→ Beware: at this stage you have exposed any weed seed that remains in the soil so be sure to give the soil some water and wait to see what germinates. Once you have weed seedlings, repeat the removal process before they set seed. How many times you repeat the process will depend on the amount of weed seed stored.
2) Chemical weeding. There are a variety of options for herbicide treatments, including:
Pre-emergent herbicides – Application of a pre-emergent herbicide will prevent any seeds present in the soil from germinating. Please be aware, there may be a lag time after the application of a pre-emergent before it is safe to sow seed.
Knockdown herbicide – If your site has existing weeds, you will need to use a knockdown herbicide that will control established weeds. Native Seeds supply an organic, contact herbicide which works by affecting actively growing green vegetation which it comes into contact with. Weed Zap is non-selective, and is a good option for those who need to control all the weeds in an area. This process can be incorporated into a regime with physical weed removal for greater success, and will also require repeated applications to reduce the number of weed seeds in the soil.
Selective herbicides – A selective herbicide has the potential to kill some weeds but not others. This takes a bit of research to firstly identify what you have growing, then deciding what you don’t want to kill and what you do and then finding the right selective herbicide. The most common selective herbicide that we would recommend simply selects for broadleaf weeds. These are very common and cheap, and will target all broadleaf weeds.
→ Here is a guide to herbicide terms if you’re new to herbicides – Herbicide Terms
3) Other weed management options.
There are many options for controlling weeds that may better suit your needs and desires including:
Weed matting can kill both established weeds and sterilize the soil for weed seed. It does so by blocking light and water from the soil and in warm conditions can bake the soil, killing any seed. Upon removal of the mat, you can be left with close to clean soil.
Burning is a useful weed management tool for killing established weeds and encouraging the growth of seeds in the soil. Repeated burning can successfully prepare your plot. Be mindful that burning is dangerous if not planned and executed appropriately. Contact your local council for information and assistance.
Other options include the use of chickens, goats and rabbits to clean up existing weeds,
smothering weeds with newspaper and mulch, and
growing a cover plant
→ An important note: If you are considering bringing new soil into your site, keep in mind that the soil you buy may contain weed seeds. Allow time to let the soil settle by watering and wait to see if any weeds germinate.
Now the hardest part is over, you have a relatively weed free plot and are ready for planting in autumn. Depending upon your needs you may want to level the site, build mounds, aerate or loosen the soil and/or install underground drippers or other irrigation. Once you can be sure autumn rain has arrived, it’s time to get sowing!