Try to aim for a seed spacing of at least
3.9 inches (10.0 cm) and sow at a depth of around
1.95 inches (5.0 cm). For optimal germination, soil temperature should be a minimum of
16°C / 61°F.
By our calculations, you should look at sowing Buerre de Rocquencourt about 14 days after your last frost date.
Buerre de Rocquencourt is tender, so ensure you wait until all danger of frost has passed in your area before considering planting outside.