When the compost is hot, it produces steam. It may feel like it’s hot, but during this cold weather, steam is very common with hot compost. The temperature of the compost when it cools is only about 105 degrees. The center of the pile may be hotter, but it is not hot enough to damage the plants.
Q: I just bought a standard pink fruit tree from a local nursery. How to prune it when it is young?
A: From your photo, it looks like you planted a fruit tree from a 5 gallon plastic nursery container. I sure hope it’s not a standard size but grafted onto M111 rootstock. There can be two beacons on the tree; one tag tells you which variety it is (eg Pink Lady), and the second tag tells you the rootstock.
The M111 rootstock is a semi-dwarf apple rootstock that allows the tree, unpruned, to reach about 20 feet tall. If left on their own roots, apple trees will grow to 30 feet or more. The M111 rootstock allows you to prune it within 20 feet.
When pruning a young fruit tree, consider that about 90% of your pruning efforts are focused on developing its structure in the first year. After the second year in the ground, the emphasis is on a balance of about 50/50 between structure and fruit production. The third year in the ground and the following years, the emphasis is more on fruit production: 90% on fruit production and only 10% on corrections to the structure of the tree.
The first year of pruning establishes five major branches from the trunk. These branches should radiate from the trunk, starting at about knee height, in different directions like the spokes of a wheel. These main branches, called primary scaffolds, should come from the trunk at varying heights up to about 3 or 4 feet for a 10-foot-tall tree. The main members of the scaffold are spaced 12 to 18 inches apart.
A central, vertical branch should extend from the top of the trunk to form the central stem. This central leader, an extension of the trunk, is pruned when it reaches between 5 and 6 feet tall on a 10-foot-tall tree.
Last year’s branches are pruned no more than about 18 inches in length. A well-trimmed sapling should allow sunlight to filter down to the trunk above and below each branch of the scaffold. These scaffolding members will eventually support smaller members that will bear fruit. Fruit development should occur throughout the tree canopy.
If you want your fruit tree no taller than 10 feet, possibly prune it to 8 feet tall during the winter. Summer growth increases the size of the canopy to around 10 feet in height. The following year, lower it again to 8 feet and let it reach 10 feet.
Q: I would appreciate your advice on the best way to irrigate my raised bed garden. Right now he is using sprinklers.
A: Switch from sprinklers to drip irrigation. Drip irrigation is more efficient at delivering water than overhead irrigation and applies that water directly to the roots, in the same place, every time.
I prefer to use half inch drip irrigation tubing with the emitters built into the side walls. Its lifespan, unlike drip, is more than 10 years. Most drip irrigation tubing is brown or black with ultraviolet light inhibitors added to the plastic. This means that drip tubing, unlike PVC, can be left exposed to the sun for many years without degrading.
When the drip tube is installed, the drippers face upwards to reduce clogging. The drip tube itself is spaced about 12 inches apart, in rows, with the integrated drip emitters triangulated from each other so they distribute water more evenly to the floor.
A ball valve is located where the water enters the drip tube so the water can be turned on or off. A flush valve is located at the furthest point. The flush valve is simply another ball valve but located at the opposite end of the bed.
This flush valve is necessary for cleaning the drip pipe after installation, repairs and on a regular basis. Along with the monthly flushing of the drip tube, the filter screen is also cleaned.
Q: How often should I add compost to my raised bed? When is it done? How much should I buy?
A: I use soil color to tell me if more compost needs to be added to the soil of a raised bed. Compost adds organic matter to the soil, and this added organic matter makes the soil a darker brown. Normally, half an inch of compost every year and mixed with the soil to a depth of 6 to 8 inches is enough.
But that’s only half of what you need to do. Organic additions to soil, such as compost, can do two things: improve the structure of the soil (make it fluffier) and add plant nutrients to the soil. Any addition of organic matter (compost, coconut) improves the structure of the soil. But not all additions are rich in plant nutrients.
Compost made from animal or human manure is generally the richest in plant nutrients. If you are vegan, compost made with lots of green vegetables and fruits and green leaves is best.
You can’t look at organic amendments and know if they’re rich or not. The only thing that tells you is leaf color and plant growth.
Soil amendments rich in plant nutrients cause plant leaves to turn dark green and increase plant growth. After the plants grow, your soil will tell you very quickly if your soil amendment was rich or not. If in doubt, use a small amount of fertilizer until you are sure.
Q: I plant a passion fruit vine near a wall that only receives spring, summer and fall sun. Or does a passion fruit vine need sun all year round?
A: If there is morning sun for a few hours, you should be fine. During the winter months, it requires less sun than in spring, summer and autumn.
On our family farm in the Philippines, the passion fruit vine is a weed that climbs everything nearby. It is a tropical plant and does not tolerate temperatures well below freezing. In our Las Vegas climate, the major problem is the cold winter temperatures, so it must be protected from the wind and cold whenever temperatures approach freezing.
The second major passion vine problem is afternoon sun damage. Passion vine, when grown in the desert, should be grown on the east side of a building with the afternoon shade necessary for it to thrive. The passion vine soil should be amended with compost and covered with wood chips.
A third problem is irrigation. Two irrigation rings of drip tubing, 3 feet in diameter and 6 feet in diameter, with 1 gallon per hour emitters spaced about 12 inches apart, should do the trick. This plant needs to be watered three times a week (possibly four times a week in extreme heat) in the summer.
Enough minutes should be used to bring water to a depth of 18 inches each time it is irrigated. If you have an existing irrigation schedule, a third irrigation ring may be needed to get deep enough water.
Q: When my mother passed away, I was given her snake plant. Potted and covered, I kept it outside over the winter in Las Vegas. The factory was in bad shape after that fiasco, so I brought it back inside. I have it outside in the shade until recently. Is it too hot for him at temperatures above 80 degrees in summer? What can I do to speed up growth and see new growth? How often to water?
A: Snake plant, also called Sanseveria or mother-in-law’s tongue, is one of the hardiest houseplants provided it has what it needs. However, the best temperature range for this is between 90 degrees and 40 degrees. Plant damage can occur at temperatures below 45 degrees, but will survive freezing temperatures.
It will appreciate the bright desert sun for only a few hours in the early morning, but after that it should have filtered out the light. It can withstand temperatures up to 95 degrees but not in direct sunlight. The best months to grow snake plants outdoors would be from early March until about the first part of May, then again in the fall, from late September to mid-November.
As it is a tropical succulent, it can tolerate slightly dry soil. Growth is on short rhizomes. Lightly fertilizing the plant with a high phosphorus fertilizer once every two months will cause it to grow faster when temperatures are between 60 and 80 degrees. Cold temperatures cause the leaves to start rolling or bunching.
Bob Morris is a horticulture expert and professor emeritus at the University of Nevada, Las Vegas. Visit his blog at xtremehorticulture.blogspot.com. Send your questions to [email protected]