Autumn Cover crops and Elephant Garlic
Summer gardens, as they are harvested, will leave bare ground which never stays bare for long.
My old Science teacher used to say to us, ‘Nature abhors a vacuum’ and that is also true in gardens as bare soil will soon produce an abundance of weeds. This is Nature’s cover crop and could be used to fortify the soil if cut down before the weeds produce a fresh crop of seeds.
The problem is that weeds tend to mature very quickly and re-seed and you are most likely to only increase your weed problems.
So what is best to do with bare ground after harvesting?
First thing would be to lightly rake the soil and then water to keep the area moist. This action will germinate many of the weed seeds that are laying dormant. Once there is a nice show of baby weeds, stop watering and allow the soil to dry for a day or two.
Then with a sharp Dutch Hoe slice the baby weeds off at ground level. If you do not have a Dutch Hoe then use a sharp carving knife to either slice or scrape off the weeds at soil level.
The foliage of the weeds is just left on the soil to shrivel up in the sun.
Now we have dealt to the weed threat to the area, we can pick a cover crop of our preference to plant.
There are a number of plants suitable for this purpose and each type will provide certain benefits to the soil. Some gardeners prefer to sow a mix of several types to obtain more than one benefit.
Alfalfa: Has a vigorous root system that aids in the break up of soil pans and brings up sub-soil minerals.
Lupin: Nitrogen fixer. (there is tons of nitrogen in the air above your gardens and this is one way of capturing it)
Mustard: Aids in weed control and assists in control of some soil fungi. Should not be planted if you have club root disease.
Oats: Supplies good mulch material.
Peas: Also an excellent nitrogen fixer, provides you with your own pea straw and likely a crop of peas for the table.
Wheat: Good for carbon and humus.
If you are just to plant one type I would suggest the peas as they give you 3 benefits otherwise mix some or all the others together and sow them, avoiding mustard if you have club root problems.
Scatter the seeds over the bare soil and wet them down with Magic Botanic Liquid which improves the germination and places extra minerals into the soil.
Lightly cover the exposed seed with purchased compost and water down. Keep the area moist.
It does not take long for the seeds to germinate and then all you need to do is ensure that the young plants have adequate moisture.
How long do you allow the cover crop to grow? That is up to yourself but do not let the crop go to seed except for Peas as you want to harvest them for the table.
At sometime you will cut the crop down close to the soil level. This can be done easily with a weed eater or a rotary lawn mower without the catcher on. Alternative to either of these would be hedge clippers.
Many gardeners dig the crop in and this is a disadvantage as digging disturbs the soil food web and is work! The best and easy way is to cut the crop down, leaving the roots to rot in the soil which is heaven for the soil life and worms. The cut crop then can be sprayed with either Mycorrcin or Thatch Busta to aid its breakdown. You may also like to throw any kitchen scraps, lawn clippings (without seeds) over the cut crop. If you can obtain any animal manure or chicken manure spread that over also. Then sprinkle a few handfuls of Rapid Lime over the area.
Next if you have an abundance of newspaper spread several sheets over the area and wet them down. Finally cover the whole area with a compost such as mushroom compost or any good purchased compost to a depth of about 20mm. Keep the area moist and it is ready to plant up when you want to.
Avoid walking on the area at all times and if the area is too wide to plant out without trampling over it divide the area into plots after cutting down the cover crop with walkways about 25 to 30cm wide.
Weedmat strips can be laid on these walkways. Then the ‘after cutting treatment as above’ will be applied to the plots not the walkways. The plots will be higher than the walkways and you may like to use a wooden frame or old bricks around the edges of the plots to obtain excellent, raised gardens.
You can before sowing your cover crop, construct plots with pathways between and then just sow the plots. The ideal No-no, is don't walk on your gardens where plants are to grow as you compact the soil and have to revert to turning over the garden by digging..

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