Poor seedling establishment is generally attributable to unfavorable soil temperatures and water stress. Vegetative reproduction is the primary mode of regeneration. In the absence of disturbance, clones increase by expansion of rhizomes. After fire or other types of disturbance, plants often sprout from the stem base, from underground rhizomes, or from unburned belowground portions of aerial stems. Fruit production strongly influenced by weather conditions, climate, pollinator availability, light intensity, genetic factors, and nutrient levels at the time of bud initiation.
Shade produced by competing weeds can often reduce fruit yields.
Cross-pollination by insects is necessary for good fruit set. By seed, following cold stratification. Seed germinates best when exposed to light. Fresh seed germinates readily at 70 degrees Fahrenheit under a regime of 16 hours light per 24-hour period. Stratification and pretreatment with gibberellin can speed germination.