Demonstration orchard to host tours

Come visit our demonstration orchard. Saturdays are a work day for our master gardener volunteers, and if you are in the area stop by and we will give you a tour. There are more than 600 fruit trees and grapes of all kinds. We are now painting tree trunks for sun protection, applying fertilizers, chipping prunings into mulch, spraying dormant oil and applying a biocontrol for peach twig borer that will attach our stone fruits later this summer. Wear your gloves and work clothes and you can help us if you like. It's the best way to learn.

We are also preparing vegetable beds and testing fruit trees and grapes with a great new composted dairy manure out of Amargosa Valley. It is one of the best composted manures I have seen. Pick-up loads are available to the general public for $30 each Saturday morning on a cost recovery basis for the orchard. The orchard is just east of the corner at Decatur Boulevard and Horse Road.

No question about it, plants are ahead of schedule. Many of our plants are about three weeks ahead of schedule right now. This is a problem. At the orchard we have our early peaches like Florida Prince in full bloom and early apricots are in what is called the popcorn stage of bloom. We generally regard Feb. 15 to be a reasonable date when the last spring frost might still occur here. If it does freeze, chances are it will be a light freeze. If we get any freezing temperatures now, a sizable amount of fruit will be wiped out.

When the flower is open even barely freezing temperatures can kill the reproductive parts of the flower and subsequently prevent any fruit from forming from that blossom. Fruit trees produce many more times the number of flowers than it needs to have a full crop. Flowers do not all open at once but even unopened flowers are tender to temperatures even a few degrees below freezing. The lowest parts of the valley usually have the coldest temperatures when it freezes.

What can you do to stop it? In commercial orchards that are sprinkler irrigated, they will begin to sprinkle irrigate when the temperature reaches about 33F. The freezing water on fruit buds helps to protect the undeveloped fruit providing air temperatures do not get below about 28F. They also use wind machines if there is a temperature inversion. Wind machines help mix warmer air above the orchard with cooler air near the ground resulting in an average temperature, hopefully, above freezing.

What can the homeowner do? Not much. If the tree or plant is small enough you can wrap it with a blanket until the sun rises. It is best to try to keep the wind off of the tree and insulated. Wrapping in plastic won't work unless you have a source of heat under the plastic.

If you are planning to plant tomatoes this spring you need to get them in as early as you can. The soil temperature at a 3-inch depth needs to be at least 60F. You can accelerate warmer air temperatures by preparing the soil and covering it with clear plastic. Make sure the soil under the plastic is moist to the touch but not wet. Black plastic also will work but not as effectively. It will not transfer heat as quickly and as deeply as clear plastic.

Loosen the soil where you are planting by double digging and incorporating a composted soil amendment and starter fertilizer high in phosphorus such as bone meal. Bone meal has long been used by farmers and home gardeners because it stimulates healthy root development. Recently questions have been raised about the amount of meat byproduct remaining in bone meal after processing and whether it is a safe product to handle. Bone meal with 1 percent less nitrogen is perfectly safe to use and any bone meal with more than 1 percent nitrogen should be avoided. Cover the area with 4 mil clear plastic for about a week.

Plant tomato transplants in a hole about 4 to 6 inches deep right through the clear plastic. You can cut a slit or hole in it. To support the sides of the hole you can use a can with the top and bottom cut out, milk containers, rolled cardboard or card stock. Buy small transplants no larger than a 4-inch pot size. The hole will provide some protection from the wind as the transplant establishes. As the transplant grows larger, remove anything supporting the soil surrounding the transplant and begin to bury the stem. The transplant will send out new roots along the buried stem and root deeper into the soil provided the soil is loose and warm.

You can cut the clear plastic away from the plant when air temperatures get into the 70s or leave it on the soil. If you leave it on top of the soil, then cover it with a light mulch or soil to keep weeds from becoming a problem.

Another problem during bloom time is the spread of fireblight, a bacterial disease, when weather is wet and windy. Fruit-bearing plants like apple and pear can be affected and nonfruit-bearing plants like cotoneaster, photinia and pyracantha also can become infected. Pollinating insects like bees and flies also can become part of the spread of this disease when they fly from an infected flower to healthy flowers.