Flowering and Pollination in Blueberry

Blueberries and bio-stimulants are a strong combination, especially during the spring, when plants are flowering, and pollination is taking place: the right bio-stimulant at the right growth stage can have a major impact on blueberry production and quality.

Spring has arrived in the northern hemisphere, with bees, butterflies and other pollinators becoming more active. Along with many other crops, blueberries rely heavily on pollinators to initiate the production of berries.

But is it only pollinators that are important, or are there other factors to take into consideration?

There are a few critical periods in the blueberry growth-cycle. The first is bud initiation in the autumn. Before the plant goes into dormancy, the plant is ‘deciding’ which buds will be vegetative, and which buds generative. The more energy the plant has, the more generative buds are initiated. The generative buds are the ones that produce flowers in spring. Poor growth in the late summer/early autumn will limit the number of generative buds, and, consequently, the yield.

Flowering is the second critical period. The flowers on the blueberry bush will pollinate and set fruit in a 2-3-week window, during which the plant experiences a tremendous hormonal shift to support this reproductive phase. In addition to the standard nutrition, the crop requires high concentrations of trace minerals and calcium. If it doesn’t get what it needs to support this hormonal shift, the plant will start to suffer and become stressed, making it an attractive food source for insects and diseases.

The third critical period in the growth cycle of a blueberry plant is fruit maturation, and the growth of new shoots.

Concerns are sometimes raised that the pollinators are not doing a good enough job, resulting in poor pollination. This can be true, of course, but there are other reasons why pollination can be disappointing, including weather conditions (temperature, rainy days, etc.), chemical residues, and the quality of nutrition in the previous (flowering) period. As mentioned above, flowering and pollination demand high amounts of trace elements and calcium, with concentrations in a flower bud at 60-80 times higher than in a leaf.
Although calcium and trace elements can be supplied using standard fertilisers, this is not always sufficient. To support the plant’s extra mineral demand:

• Use the root enhancer Vidi Parva in the spring to improve root mass and quality
• During the crucial flowering and pollination period, make 1-2 foliar applications of Vidi Terrum (to meet the high demand for trace elements) and Veni Calcium (calcium is very important in the first development stage after pollination); Vidi Terrum contains seaweed extracts, in a plant-based form for rapid assimilation, and Veni Calcium is easily absorbed by the plant due to its unique composition - using a foliar application ensures it is directly available to the plant

These applications will have a very positive impact on plant performance. Once the number of generative buds has been optimised in the autumn, active nutrition has been ensured, and balance in flowering and pollination has been achieved, everything is ready for a good harvest.