Passion Fruit that is winter hardy to -4F, or about Zone 6b? Yes, it’s true. The Swiss breeding company Lubera has been growing and selling its hardy Cooltropics® Eia Popeia® variety in Europe a few years now and this vining, climbing, flowering and fruiting plant is indeed able to survive in this non-tropical environment. And Eia Popeia isn’t their only variety. They just introduced Snowstar—a gold medal winner at France’s annual Innovert new plant competition—and their Rhine Valley breeding gardens are filled with different varieties, some of which will come onto the market in the next few years.

What Impacts Winter Hardy Passion Fruit

Turns out these winter hardy passion fruits, Passiflora incarnata, are originally from here in the U.S. and are hardy to as far north as Missouri and Pennsylvania. So, they already have some winter hardiness “built in” as part of their genetic makeup.

But still, some northern European gardeners have not had success with growing these winter hardy passion fruits. What might deter passion fruit from growing its best in northern climates? Here are a few suggestions from Lubera’s passion fruit breeder, Raphael Maier:

• It’s a perennial. Passion Fruit is a perennial, so keep in mind that its aboveground foliage will die during the winter and its roots will go dormant.
• Have patience. Many perennials will emerge in spring as early as March and April. Passion fruits “sleep” a little longer. Don’t expect to have them emerge until May.
• It loves warm weather. Passion fruit really starts to grow in warm temperatures. It hits its stride when temperatures are in the 70s. According to the breeder, this might mean that in some very northern regions, passion fruit might not grow well or even emerge from the ground if there is a cool summer.
• Snails love it. Snails will devour a just-emerging passion fruit plant in no time flat.

Tips for Growing

Raphael Maier also had some tips for helping get Eia Popeia and Snowstar through the winter:

• Choose a sunny spot. Plant your winter hardy passion fruit next to a south-facing wall. This helps direct sun and warmth to the heat-loving plant for quicker spring emergence and summertime growth.
• Protect against snails. Use snail bait or other methods of snail prevention.
• Well-draining soils. Well-draining soil helps prevent fungi damage, promotes root growth and helps the soil warm up faster in spring.

I always thought that something with such a beautiful and unique flower and such an exotic fruit couldn’t be grown in a place where winters were so cold and dreary. Now we know! I’m not sure if edible passion fruit plants are available in the U.S., but if you find one, give it a try.