Wet the soil first, lay down the cardboard, cover the cardboard and let it rest. Whether you will be able to plant this fall or not depends on the Soil Food Web you have now. If that is pretty active, functioning well, there is a good possibility you could. But if the soil does not have a functioning Soil Food Web, if the soil is not in a good, healthy state now planting this fall would not be a good idea, waiting at least until spring would be better.

Thank you for your response Kimmsr. I am quite out of my league here, and had to look up Soil Food Web the net. This area has been 'idle' for the past year. During that time, much of the bed of cedar leaves have decomposed and I have two tomato plants growing quite happily there. It is very dry and it drains quite well in a pot, but does not get 'wet' easily. You might understand what that means: sandy, no humus? Because of the dryness, there are no earthworms but there are slugs there which have attacked my seelings which are being held there until fall. I don't know what that says about the Soil Food Web, if anything. I have done a little experiment I read about some time ago - shook some soil up with water in a jar and I am letting it settle. So far (after 8 hours) there are four layers:the bottom layer (dark earth); a very thin layer of lighter coloured stuff; the water layer, and a floating layer which I believe is the residue of cedar leaves that have not yet decomposed. As I recall, it should settle into more distinct layers than that. The area will be much more moist in future because it will get a good snow cover, and will be open to the rain. I will start in sections and follow your directions. Please let me know if there is any more information you can provide. Thank you.
Northerner.

I'm not sure what AgCanada does for the average homwowner but a good, reliable soil test would be a good starting point here and they may be able to direct you to where in Canada you can get that done. Also these simple soil tests,

1) Structure. From that soil sample put enough of the rest to make a 4 inch level in a clear 1 quart jar, with a tight fitting lid. Fill that jar with water and replace the lid, tightly. Shake the jar vigorously and then let it stand for 24 hours. Your soil will settle out according to soil particle size and weight. A good loam will have about 1-3/4 inch (about 45%) of sand on the bottom. about 1 inch (about 25%) of silt next, about 1 inch (25%) of clay above that, and about 1/4 inch (about 5%) of organic matter on the top.

2) Drainage. Dig a hole 1 foot square and 1 foot deep and fill that with water. After that water drains away refill the hole with more water and time how long it takes that to drain away. Anything less than 2 hours and your soil drains too quickly and needs more organic matter to slow that drainage down. Anything over 6 hours and the soil drains too slowly and needs lots of organic matter to speed it up.

3) Tilth. Take a handful of your slightly damp soil and squeeze it tightly. When the pressure is released the soil should hold together in that clump, but when poked with a finger that clump should fall apart.

4) Smell. What does your soil smell like? A pleasant, rich earthy odor? Putrid, offensive, repugnant odor? The more organic matter in your soil the more active the soil bacteria will be and the nicer you soil will smell.

5) Life. How many earthworms per shovel full were there? 5 or more indicates a pretty healthy soil. Fewer than 5, according to the Natural Resources Conservation Service, indicates a soil that is not healthy.

can provide you with some good information about your soil that you should know.

g'day northener,

how would raised beds go? sounds like an ideal spot, soil test is optional.

check our pic's and story see how we do it and the results we get.

len

Here is a link that might be useful: len's garden page

Thank you both Kimmsr and Len for your valuable information. Kimmsr, your information appealed to me because I am a trained Analytical Chemist and work as a Tester in IT, so I appreciated detailed test instructions. Just glancing at them, and the little soil & water test I did, I know I have mostly sand there,so I have lots of work to do before I can plant.
Len, I had a quick look at your 'Bale' bed and while I like the 'live' look of it, I don't think I have enough room for it, and my area is not in full sun - it just gets afternoon sun about half way in, so it will be mainly a green space. But I maybe able to apply some of the concepts to a raised bed with a different kind of enclosure. Great site, though, and I am sure I will be browsing it fairly often in the future. Thank you for all the help, as I said, I am quite out of my league when it comes to soil.
Northerner.

Many people think soil testing for nutrient load is optional, but anyone the least bit concerned about the environment they live in should be concerned enough about putting nutrients that are not needed into soils so those nutrients can then pollute the environment we live in even more. Nitrate and phosphorus poisoning of our drinking water is epidemic and the cause is people unnecessarily putting down too much fertilizer.