Q1: The cherimoya has had a number of flower buds this year, none of which has set fruit. I’m aware that they need to be hand-pollinated. But where is the pollen? I don’t see separate pollen bearing structures, and at no stage of the female flower bud maturation cycle do I see obvious pollen. What am I missing or where do I look?
A1: Let me start by saying the Cherimoya in question is probably to young to bear fruit. The flowering cycle typically begins in mid-spring and continues throughout summer. The flowers are perfect with both male and female parts in each flower. As you mentioned self pollinating is not consistent especially in climates lacking the humidity needed to lengthen the time the flower is receptive to proper pollination. That being said, the best time to hand pollinate the flowers is between 4 and 7 P.M. The best time to collect pollen from the male flower is when the petals are almost completely open yet have not begun to show signs of drying or discoloration.
This is done by using a small black container to contrast with the light whitish color of the pollen. Lightly tap the flower holding the container underneath to collect the pollen. Using a small 1/8th wide brush lightly moisten the tip and dip in container to collect a tiny amount of pollen. The female flower stage is recognized when the petals are only just beginning to open at the tips. You may spread the petals open slightly to allow the entry of the brush tip to come in contact with the base of the flower where the receptive stigma is located. Touch the base of the flower a couple of times only as a very seedy fruit will result if you over do it.
I like to snap one of the petals in half to mark which flower I pollinated. I do not store pollen and always collect it 10 minutes before I pollinate. Sometimes it is difficult to find pollen but that will change as there are cycles where much overlapping between the male and female stage flowers occur. In other words, there are periods when all you can find are either male or only female flowers but be patient as soon there will be both stages available at the same time. Remember, there is plenty of time to pollinate these flowers as the blooming cycle lasts for over two months.
If you spread out the pollinating process an extended fruit harvest could be achieved from late winter into early summer and beyond. I hope that helps.
Q2: About the Strawberry Guava – it flowers continuously and grows vigorously, but no fruit has set. Any ideas about it?
A2: The strawberry guava will fruit heavily perhaps this year or next. If you have been fertilizing this plant every month since you purchased it from me and it has responded by growing significantly, than I would stop feeding it any nitrogen and switch to a bloom only fertilizer.
Thanks again for your response (sent a year ago) which is clearer than any of the several explanations I had previously found on the web. I’ve got at least 20 fruit set on the tree this year, starting from the first week of June, and new flowers continue to develop. I make rounds of the tree about every other evening. There isn’t much pollen per flower, it isn’t very obvious, and doesn’t seem to be available for very long. All that said, most of the flowers I’ve attempted to fertilize seem to have caught. I’ll probably have seedy fruit! Skill will have to come with practice. The limbs would break if all the set fruit matured, I’ll deal with that problem if it happens. The guava and kumquat we bought the same day (Feb 2007 if I recall correctly) are doing well. The strawberry guava, also mentioned below, continues to grow and bloom. No fruit set on it yet but as you say that will come in time.
Thanks again for the useful information you sent.