Now, there are very few people from experience that don’t like eating Passionfruits in some form or another. Common, easy to grow and sweet, these relatively thirsty climbers have been grown by households in Australia for a long time.
When you go to acquire an edible Passionfruit plant in Australia you have a few main options; the variety – Black, Panama, Banana, and whether it is grafted or un-grafted. First available in the season are the grafted var’s as the non-grafted take a little longer to get going. You may be wondering… whats the real difference?
I personally avoid buying grafted Passionfruits as the rootstock used is from an exceptionally weedy Passionfruit variety from South America called Passiflora caerulea. The reasons given for its use as a rootstock is that it is cold-hardy and disease resistant, but it also readily sends sub-surface runners and shoots out which have to be constantly kept back or it will quickly overtake the top of the graft (desirable bit) and probably a lot more of your yard! Vigorous to the point that it will smother vegetation in yard and bush alike, it also produces natural cyanide in its stems, leaves and immature fruits so don’t let livestock or other animals (incl. children) eat it either.
I feel that part of the reason Blue Passionfruit is so frequently used as rootstock may be that a single plant will produce 1000 plants for grafting onto due to its running habit and that saves money, effort and time growing 1000 whole other rootstock plants as grafting fodder.
If you live in an area like Victoria or inland that has much colder periods of the year, the
Blue grafted varieties may be right for you. The rootstock being a bit less excessively-vigorous in the cool but you’ll still need to keep an eye on those runners as it can still be a weed in these areas. Possibly growing these in a container may help you to restrict much of this unwanted spread.
If you live in an area classed as warm-temperate, subtropical through to the tropics you’ll be able to grow non-grafted Passionfruit quite easily and with much less maintenance. The trouble more seems to be keeping water up to them in a low input system. Ie; minimal fertilisation, watering etc. tending to do much better in a partially sheltered understorey situation.
The main basis for this post is that i’m growing a native Passionfruit (Passiflora herbertiana) which is a bushfood local to the NSW east coast and ranges, into Queensland. The fruit itself is small, edible and sweet but has a distinct aftertaste. I havn’t heard of anybody trying this but I wonder if using this native species as a rootstock could reduce the relatively high water requirements of the cultivated Passionfruit varieties. At least for the areas where the native has natural distribution. I believe Passiflora herbertiana is not as cold hardy as Blue Passionfruit but having evolved in an arid country like Australia I assume it is more ably adapted to drought and minimal irrigation. Also the risk of it taking over or becoming an environmental weed is about zero.
Currently just an idea, if you’re reading this and have any input or thoughts I’d greatly appreciate the discussion. 🙂