There has been a major problem with the flowering of the almond crop in Australia this year. Normally flowering is strong and yields are good but this year the bloom of the principal variety, Nonpareil, across the entire almond industry has been very patchy and very light, the lightest we have seen for a very long time. However, flowering of the pollinator variety Carmel was good. The Nonpareil flower buds just didn’t seem to form, were aborted through the development phase or in some cases were “reversed”. We have shoots that have single bud positions which are vegetative only, we have single bud positions that when magnified seem as though there were lateral buds due to the presence of what looks to be a scar where they were aborted, and we have single bud positions with two shoot positions, central and lateral. See photos attached below.
This is very strange and we are not sure what “stress” (or something else?) has caused this. It may have been caused by the wide-spread, premature defoliation we had last harvest due to rust (we had quite a wet summer and harvest period) and therefore not the capability to allow/facilitate the flower buds to develop early in the development cycle. Furthermore, the premature defoliation was followed by re-shooting of new vegetative shoots and in some cases new flowers before the season had finished. See above image.
We don’t think it is lack of chill, even though this wasn’t that good this winter, as Carmel was not affected (in fact it had a huge flowering) and to my understanding requires more chill than Nonpareil.
Does anyone have any suggestions on the cause of the problem and how we may address it in future?