Nellie Kelly is most famous for its unique method of grafting popular passionfruit vines onto a hardier rootstock vine. This creates plants that are less susceptible to disease, pests and frosts and allows for greater fruit production.
The official rootstock of all grafted Nellie Kelly Passionfruit vines is the blue passionfruit (Passiflora caerulea) which replaced the original rootstock of banana passionfruit (Passiflora mollissima) over sixty years ago.
While Nellie Kelly’s grafted passionfruit vines have obvious advantages there are certain circumstances where the non-grafted varieties are more suitable. Nellie Kelly’s non-grafted Black and non-grafted Banana Passionfruit vines are recommended for gardens with coarse or sandy soils where grafted vines would be prone to suckering. These non-grafted vines also thrive in warmer, tropical areas where frost is not a problem.
The vine is best planted facing north or where it can get the 4 to 6 hours of direct summer sunlight it needs to ripen the fruit. Planting in a shadier position will result in lots of green foliage but unripe fruit. The best time to plant your Nellie Kelly Passionfruit vine is in early spring after the cold weather has passed.
Fertilise your passionfruit vine early in the spring after a thorough pruning and then again after the fruit has been picked. Over fertilising will cause the flowers to drop off and prevent fruit from forming.
For new plants, fill the bottom of the hole with some blood and bone first, and for developed plants spread the fertiliser over a wide area around the base of the vine before gently raking in and giving a light water.
Fertilise after pruning by spreading a good top-dressing of blood and bone or aged chicken manure in a wide area from the base of the stem. Rake this in lightly and water.
Flowers generally appear in mid-spring before setting to fruit in early summer. Application of superphosphate around the base of your vine will encourage flower growth, while adding potash will help them set. The fruit that forms needs several solid days of direct summer sunlight to ripen, resulting in a darker, wrinkly skin.Always water widely around the base of your passionfruit vine while fruit is ripening, especially on hotter days. Lack of sufficient water during this period results in fruit with poor quality pulp and little juice.