Hi Hugh, could you explain why you picked option 3, the only reasons that i can think of is
1/stopping the leaching of nutrients.
2/the heating up of the soil in the spring to allow the sowing of seed and plants early.
Will the plastic still allow the soil to brake down the same as if it had no plastic on, and will the soil have to be cultivated to a fine tilth to allow sowing.
3/ would you plant through the plastic,and use the plastic as a mulch to stop weeds growing all year long.
thanks,
windy.