This is a relatively recent addition to the Petunia range, and is generally treated as a half hardy perennial in the UK.
As with most Petunia, they prefer a light well drained soil in a sheltered sunny spot,
alternatively, use them as container or hanging basket plants.
They are quite tolerant to wind & rain, and provided they are deadheaded regularly, will flower until the onset of frost. After which they should be lifted, potted up, and placed under the greenhouse bench for the winter.
Propagation x cuttings
Plants should be watered and placed in a warm spot in February to encourage new growth.
In early March take 50-60mm long cuttings, cutting the stem under a leaf node, remove the lower leaves to expose approx 25mm of stem.
Dip the stem in a rooting powder/liquid, and insert in to pots/trays containing a 50-50 peat* and sand mixture.
*Multi-purpose compost can be used in lieu of peat.
Maintain a minimum temperature of 10*C (50*F) when rooting the cuttings, a little bottom heat is a distinct advantage at this stage.
Rooting should take place in about 10-14 days.
When rooted pot up into 70-90mm pots of Ji.No1 potting compost (or similar) and gradually harden the plants off, by subjecting them to cooler conditions until planting out time in May, or when all risk of late frosts has past.
Propagation x seed
Surfinias; are produced from cuttings under copyright, and seeds can't be purchased commercially,however by saving seed after flowering, one can sow these in Feb/March.
*Please note, the resulting plants may not come true to variety.
Sow the seed in pots/trays of seed compost in February/March, maintain a minimum temperature of 15*C (60*F) until germination.
When seedlings are large enough to handle prick out into 70mm pots of JiNo1 potting compost (or similar).
Gradually harden the plants off by subjecting them to cooler conditions until planting out time in May, or when all risk of late frosts has past.