Aim to sow
0.49 inches (1.25 cm) deep and try to ensure a gap of at least
5.85 inches (15.0 cm). Soil temperature should be kept higher than
5°C / 41°F to ensure good germination.
By our calculations, you should look at sowing Vreeken about 60 days before your last frost date.
As Vreeken is tender, ensure temperatures are mild enough to plant out - wait until after your last frost date to be on the safe side.
By our calculations, you should look at planting out Vreeken about 45 days before your last frost date.