The summer berry harvest season is bittersweet. We love all the fresh, ripe fruit while we have it, but the season is over in no-time. One thing I like about growing raspberries; beyond just plain old liking raspberries; is they can be a “have your cake and eat it too” situation. Thanks to primocane fruiting varieties you can enjoy fresh summer-bearing raspberries now and also enjoy another crop in early autumn. How is that?
Biology of a Raspberry Plant
Well, I’ll explain. The raspberry crown that you are growing in your garden is a perennial plant. However, the cane that grows from it and bears fruit is typically a biennial. During the first year of its growth the cane is vegetative and known as the primocane. (“Primo-“ deriving from primary or first.) That cane overwinters and becomes fruit-bearing in its second year. At that point it becomes known as the floricane. (“Flori-“ meaning flower; which leads eventually to fruit-bearing.) Once the floricane has borne fruit for a season it is no longer productive and dies. It should be pruned out after harvest. New primocanes are already growing from the crown to perpetuate the cycle fo fruit-bearing. The traditional raspberry varieties have been of the summer floricane-bearing type. Now gardeners have an additional new type of raspberry to try.
By a minor fluke of nature, over time several raspberry varieties were discovered that, in addition to the normal floricane crop, put out a crop of fruit on the primocane. That is how we’ve gotten to have our pie and eat it too! Primocane bearing varieties can be managed in several ways, depending on when you want their crop:
- They can be pruned like the summer-bearing varieties, allowed to produce a primocane crop, and then left to produce a floricane crop the following summer. The primocane crop will grow on the tips of the canes. After the second crop, prune out the spent floricanes.
- They can also be grown just like the traditional floricane bearing varieties; harvesting only the summer crop and then removing the spent cane. This summer crop will normally produce more volume than the fall crop. You can usually expect a ratio of 2:1 summer to fall harvest yield.
- Finally they can be mowed to the ground annually and grown for just the late summer, early fall crop. This method simplifies maintenance but more care must be taken in choosing varieties. It is important to select a variety that will produce and ripen the crop before fall frosts occur in your area.
Currently there are only red and golden primocane raspberries, no black or purple varieties. Heritage was one of the original primocane varieties, but was not suited for northern regions since it ripened fairly late. Today there are earlier ripening varieties. Some of the currently popular primocane-bearing red raspberry varieties include:
- Autumn Bliss ripens 10 to 14 days before Heritage.
- Autumn Britten
- Crimson Giant ripens after ‘Heritage’ and extends the season until late October. It is only suitable for areas with very long growing seasons.
- Heritage is considered the standard fall bearing red raspberry variety. It is not recommended for regions with cool summers or a short growing season with frost before September 30
- Himbo Top
- Jaclyn ripens 2 weeks before Heritage.
- Joan J
- Prelude also bears a very late season primocane crop. Best grown in zone 5 or higher. It does produce an early summer season floricane crop.
Yellow Primocane Raspberries are color mutations of red varieties. The most popular are:
- Fall Gold (aka Goldie) is an amber sport of Heritage
Recent breeding efforts have also produced several primocane-bearing blackberries. They are slowly finding their way onto the market and could be an answer for northern areas where ripening a blackberry floricane crop is challenging due to the short growing season. Some varieties worth trying include:
- Prime-Ark 45 is tolerant of summer heat and suited for growing in the southern climates of zones 6–9.
- Prime-Jim is quite thorny. It has a high chilling requirement, so is not suited for the most southern growing regions.
- Prime-Jan also has a high chilling requirement, so is not suited for the most southern growing regions.
Enjoy your bramble harvest now. Plant some of these new primocane fruiting varieties next spring and you can have your fresh bramble berry pie in two seasons.
For complete information on growing both summer and fall fruiting brambles buy The Backyard Berry Book.