The University of Nevada Cooperative Extension’s second master food preserver class is being offered for two full days April 28 and 29 at the Lifelong Learning Center. We are now taking registrations for the class. To get more information, call the master gardener help line at 257-5555 or email me at firstname.lastname@example.org.
Q: I saved some papaya seeds last year and planted three of them in the spring. To my surprise all three began to grow . I’d like to transplant them into individual 15-gallon pots. I read where they do not like to be disturbed once they start growing. What might be the right time to attempt that? What would be the best way to keep them through the winter? And what are the chances they would ever bear fruit some day?
A: Master gardeners who attend my classes are very familiar with me saying, “You can grow any plant in the world in Las Vegas. It depends on how much time, energy and money you want to use to make it happen.” Rare fruit growers in Phoenix grow papayas outside with some freeze protection applied during the coldest part of the winter. We are not Phoenix but we do have some similarities.
This is what you need to know about papayas to be successful. Papayas prefer rich, tropical, acidic soils. They will not withstand temperatures much below 32 F . Papayas do not like direct sunlight from the late afternoon sun and would prefer about 30 percent shade if in full sun. Papayas will die growing in soils that do not drain easily, but also do not tolerate dry soils.
They are heavy feeders and require continual applications of small amounts of fertilizer. They need both male and female flowers to set fruit. Sometimes this happens on a single plant and other times it requires male and female plants. Plant several so that your chances of getting male flowers is increased.
They are normally started from seed and, as you found out, the seed germinates easily. Most of our papayas come from Mexico due to production costs. They should transplant fairly easily into 15-gallon containers if you are careful and stake them in the new containers to keep them upright and wind resistant.
Keep them lightly shaded until the roots have re-established in the container, for about one month. They should be able to handle more sunlight after this.
Some varieties may become damaged anytime the temperature reaches about 45 F; others are more resistant to this type of chilling injury. They will not handle any freezing temperatures and they become stunted at temperatures even slightly above this.
I have no experience growing them here but it’s reasonable to assume that they would handle morning to midafternoon sunlight but not late afternoon. They will handle some light shade but will probably not do well in fruiting if the shade is too much.
These trees produce at a very young age , but they are also very short lived. Of course, it would be best if they were in a greenhouse here and handled as a tropical plant.
No one is certain how the fruit is set, whether it is by wind or by pollinators. If you’re lucky enough to keep it long enough to get flowers, you may have to do some hand pollination if you do not get fruit set. Your biggest challenge will be to keep it from getting hurt during the winter and still provide enough light during the summer to encourage flowering and fruit set.
Q: Our mature apricot tree has been a good producer of sweet apricots during the seven years we have owned the house. This year the apricots were not sweet and there is sap coming out of one of the limbs. Now, after harvest, several limbs are dying. I am attaching a photo of the damage. Is there anything we can do to save our tree?
A: Sap coming from the limbs is usually an indication of stress or damage of some sort. Apricots are not as notorious as peach or nectarine for getting borers, or boring insects, in their limbs. Damage from borers is typically on the upper surface of limbs because of sun damage and its very thin bark. Damage from sunburn borers can cause sap to flow near the damaged area.
Your picture seems to indicate sun damage but it could also be damage from boring insects. If this damage were from boring insects, by late June or July you would see a limb with leaves that have totally turned brown and perhaps limb death. Branch death would be a clear indication of borers and the limb should be removed.
There is no chemical spray that you can safely apply to apricots for controlling borers. We usually rely on whitewashing limbs and the trunk with diluted white latex paint and removing limbs that are heavily damaged. This white latex paint is diluted with an equal amount of water, mixed and applied with a brush or sprayer on the upper surfaces of limbs, and western- and southern-exposed areas of the limbs and trunk. This white wash helps decrease damage from sunburn and subsequent infestation by boring insects .
Q: I planted melon seeds from the orchard and the plants look healthy. I also planted some Desert King watermelons figuring they would be a good variety for here and they look good, too, but I only got one melon. Why? I figure it might have something to do with lack of pollination? Can I pollinate them by hand and is there a special way I have to pollinate them? Could they be lacking a fertilizer? Nutrients? Too hot?
A: You are probably right; it’s most likely a lack of pollination. It would be a lack of pollination if you saw lots of flowers but no fruit set. If you did not see many flowers, it is possible they could have been overfertilized with nitrogen. This might produce a lot of vine growth with fewer flowers.
If you get lots of early vine growth and flowering was delayed, then the flowers may have set when it was hot, thus reducing fruit set. Normally, if there are enough bees and bees have access to the flowers, pollination should be good. You should not have to do this by hand. But hand pollination is an option.
You have to learn the difference between the two flowers, male vs. female, sex them, take a delicate paintbrush, such as horse hair, and transfer the pollen from the male anthers to the female stigma at the top of the female organ. Select only large, fresh and healthy flowers when you do the transfer. Do it in the early morning hours when bees are normally working as well.
Another option is to attract more bees into your yard. You could do this by planting more flowers that bloom during the same time as you melons. Or, you can put in bee boxes.
Bob Morris is an associate professor with the University of Nevada Cooperative Extension. Direct gardening questions to the master gardener hot line at 257-5555 or contact Morris by email at email@example.com.