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Nearly all caneberry cultivars are “self-fruitful.” This means that self-pollination or pollination by the same cultivar will result in the development of fruit. Caneberries can be wind or insect pollinated. Insect pollination, particularly by bees, can improve fruit size and set. Commercial growers should consider placing one or two hives of honeybees per acre. The hives should be grouped into units of five or ten hives per location.

The time from flowering to fruit harvest can vary significantly for both blackberries and raspberries. Keep records of peak bloom and harvest each year to help manage your harvest. See Table 12-1 for an example with blackberries. Over time, you should be able to estimate when the harvest will start, peak, and end. Simply record the dates that you observe at the stages of development from flowering through fruiting on three or more fruit. We suggest flagging the fruit with colored tape and returning to the same fruit each week to observe and record changes (See Figure 12-1.) Flagging three or more fruit ensures that you will have fruit by the end of the season to observe because fruit can be lost from accidental picking or other mishaps. It would be helpful to print out a copy of Table 12-2 to use as a record for each cultivar.

Table 12-1. Days from flowering to fruit development of erect thornless floricane-fruiting blackberries in Clarksville, Arkansas. *
Stage Osage Apache Natchez Navaho Ouachita
50% bloom 2 May 8 May 29 April 7 May 6 May
Peak fruiting 26 June 6 July 17 June 1 July 29 June
Number of days 55 59 49 55 54


Clark, John R. 2013. "‘Osage’ Thornless Blackberry." Horticultural Science 48, no. 7: 909-912.

Clark, John R. and James L. Moore. 2005. “`Ouachita' Thornless Blackberry.” Horticultural Science 40, no. 1: 258-260.

Table 12-2. Monitoring flower to fruit development in your field. Enter the dates that you observe each stage for three flowers of each cultivar.
Stage Flower 1 Flower 2 Flower 3 Comments
Full bloom
Fruit development from flowering to ripe fruit.

Figure 12-1. Images of Natchez blackberry flower, green fruit, red fruit, and black fruit. This fruit took 51 days to mature from an open bloom to a fully ripe fruit.

Source: Ashley Whitaker and Daniel Shires.


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As the fruit ripens, it grows in size and weight. The color changes from green to red to black. Blackberries need 45 to 60 days to mature after they are pollinated.


Skip to Raspberry

Flavor and sugars increase as the fruit grows in size and weight. Color changes from green to light red to red. Raspberries mature approximately 30 days after they are pollinated. Ripe fruit separates from the plant, which leaves the torus (or core) attached to the plant. About 85% of the fruit size is gained in the last days of maturation. Development at this time depends on adequate supplies of carbohydrates and water. Any limitation will adversely affect fruit size.


Extension Specialist (Small Fruits Breeding and Production)
Distinguished Professor, Horticultural Science
Extension Specialist, Associate Professor
Department of Horticulture, University of Arkansas
Extension Assistant
Horticultural Science

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Publication date: Feb. 23, 2023

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