A successful crop cover experiment

The small potato plants in the front of the picture were covered with straw; the much larger ones at the back  (planted on the same day) were covered with microclima cloth.

The 'spud gap' has opened up in the Eco Garden (and kitchen). We ran out of home-grown spuds about a month ago, while in the ground the two rows of 'Liseta' potatoes I planted on 29 August have only been up for three weeks. In one row the plants are almost twice as large as in the other one, and the difference is that they were covered with microclima cloth from the day they were planted until the leaves started pushing against the cloth. The other row was covered with straw. When I pulled back the straw I found that soil in that row was wetter – and cooler. I removed the microclima cloth ten days ago, and although the weather since then has not been very warm, the bare soil around these spuds was much warmer than the soil under straw. The cloth-covered spuds also came up over a week earlier than the straw-covered ones, and have definitely got a head start.
 
The same goes for carrot seeds sown in a three-covers experiment. The ones covered with microclima got their first true leaves a week before those without any cover at all. The same goes for the straw-covered row. Even worse, the seed leaves there were long, pale and skinny (etiolated I believe is the technical term) because of being forced to come up through the straw.  So I have now proven for myself two things I had to take on trust before. Firstly, microclima cloth is worth the expense (and it is not that expensive) in terms of giving open ground plants a head start. We will be eating baby new potatoes at least a week earlier than we would have otherwise. Secondly, what I have read about not mulching the ground in spring because it keeps it cooler is true. So I'll be saving the straw mulch for summer time, when I want the ground to be wetter, and not too hot.

The carrot seedlings in these rows are a bit too small to photograph yet, but trust me - the ones under the cloth (draped behind) got their true leaves a week earlier than the ones sown in bare soil (in the front).