Monday, September 29, 2014

Avocado - First Flowers and Fruit


Fig.1  Indeterminate inflorescence


At the time when I was about to give up hope of ever making homegrown-homemade guacamole, our avocado tree bloomed this year - hope has dawned.  This is the same avocado tree  that I wrote about earlier. Like all other trees in my garden I expected this avocado to bloom sometime; but because it took almost nine years before the first flowers appeared, I was surprised to see panicles (clusters of flowers in one stalk) of flowers last spring.  I guess this is the thrill of growing fruit trees from seed. 

There are two types of avocado inflorescences (flowers) - determinate or indeterminate. Indeterminate inflorescence, terminates below a vegetative bud (Fig. 1), which according to the UC-ANR, is more common in this area.  In the case of determinate inflorescence, flowers appear at the terminal end of the flower-bearing shoot.  Avocado inflorescence develops in panicles of up to hundreds of flowers.  For the tree in my garden, there were very few flowers per panicle - which is not surprising since this is only its first blooming year. Maybe the second year will be better.  

Fig. 2   Cobweb-covered panicle.


After flowers, the next thing to look for are fruits.  There was one fruit that developed. The one and only (Fig.3).  Why?  Pollination is the major determinants of productivity.  Flowers have to be pollinated prior to fertilization and fruit setting - usually, insects play a huge role in this process. Close-up picture of the flowers on Fig. 2, gives an explanation to the singular fruit (Fig. 3) on the entire tree.   The flowers were covered with cobweb prior to anthesis (period when flower is fully open and functional). Any insect attempting to visit the flowers is in for a deadly trap.  Regardless of the complexity of the avocado pollination process, this situation alone seems enough to abort pollination.


Fig. 3    The one fruit.


Lessons learned:  
1.  Under local conditions, avocado takes nine years from seed to flower.
2.  Fruiting can happen in this area.
3.  A second tree is not a requirement to pollination.
4.  Spiders can hinder pollination.  :)



No comments:

Related Posts with Thumbnails