An update on new season blueberry feeding by soft fruit agronomist, Dr Neil Holmes.
Figure 1 – early bud development in blueberries
Blueberries are currently breaking dormancy and first flowers are present at early sites. It is likely that where tunnel skins have been removed the substrate has been flushed with rain water and therefore the feed in the pots is relatively low. Consequently, it is time to begin blueberry feeding now that the top growth has started moving.
OMEX can supply two specialised blueberry feed mixes of either O-Mix 18-18-18+1.6MgO+TE or O-Mix 15-15-22.5+1.6MgO+TE (see table for specific nutrient inclusion). Both deliver high quality soluble nutrition and contain a greater N-P-K content than similar blueberry feeds on the market. Hence, there is less reason to supplement the blended feed with additional “straight” water soluble fertilisers.
Figure 2 Nutrient content of OMEX blended soluble fertilisers for blueberries
Due to low ambient temperatures, it can be difficult to feed the blueberry crop as often as desired for fear of quickly saturating the substrate with too many fertigation cycles. Under these circumstances, applications of Sulphomex can deliver fine particles of ammonium and sulphur to the bush supporting early season protein synthesis. As the slide below shows, mixing elemental sulphur and applying it to the canopy is likely to leave sulphur deposits on the foliage, increasing the chances of a phytotoxic reaction by the plant. Sulphomex applications in comparison, do not leave a deposit on the leaf and can be combined with a number of plant protection products, the compatibility of which can be checked here.
Figure 3 A demonstration of the Sulphomex coverage on a leaf (left) compared to an elemental spray treatment (right).
For more information on blueberry feeding, or any of the above products, contact your local technical manager here.