Mâche, also called corn salad or lamb's lettuce, is the hardiest salad green there is — small nutty rosettes that shrug off hard frost and sit happily under snow. It is the crop that fills the hungry gap, sown in autumn and picked when nothing else is standing, or overwintered for the very first cutting of spring.
It germinates in cold soil and asks for little. Sow it thickly in a fine seedbed in early spring or, better, from late summer into autumn for fall and winter picking; the latest sowings overwinter as tiny rosettes and surge into growth as the days lengthen. Harvest whole rosettes at the soil line once they reach a few inches. The flavour is mild and faintly nutty, best in cold weather — it turns bitter and bolts the moment real heat arrives.
Downy mildew
Yellowing on top of leaves with grey-purple fuzz underneath. Spreads rapidly in humid conditions.
Remove affected leaves. Improve air circulation. Avoid overhead watering. Copper spray as preventive.