Sow the seed thinly in pots or trays on a windowsill or in a greenhouse in a good quality, finely sieved, moist compost.
Sow at a depth of approx. 0.23 inches (0.6 cm) and aim for a distance of at least 1.95 inches (5.0 cm) between French marigold plants. Soil temperature should be kept higher than 15°C / 59°F to ensure good germination.By our calculations, you should look at sowing Petite Orange about 49 days before your last frost date.
Transplant seedlings spacing them 5cm apart in trays and grow on. Acclimatise the plants to outside conditions and then plant 15 – 23cm apart in a sunny place.
As Petite Orange is half hardy, ensure temperatures are mild enough to plant out - wait until after your last frost date to be on the safe side.