Harvest Oranges Before a Hard Freeze

Q. After 6 years, I am finally getting  oranges. They are turning orange and I have been told not to pick them until mid January. Is this right or can I pick them now (mid-December)?

A. Different varieties ripen at different times. I would sample one now and if it tastes good to you then harvest the others at the same maturity. If it is not yet to your liking then wait a bit but if temperatures drop to the mid-20’s then the fruit might freeze. In the Las Vegas area we get our coldest weather NORMALLY from mid-December to the end of January.

Play it by ear a bit right now but normally they would be ready right about now. You do not want to wait too long because fruit remaining on the tree can interfere with new flower production.

I copied and pasted this citrus calendar from the University of Arizona pdf document you can download from HERE. These are the approximate harvest dates (this is for Maricopa County, aka Phoenix area). We are a bit colder so harvest times can be a bit later. However for areas like Laughlin and Bullhead City they would be on the mark.

Note: I am recommending citrus in the Las Vegas area in only warm microclimates or protected from winter cold and winds.

The chart below I copied and pasted from the University of California Riverside pdf document you can download HERE.  This tells you the critical temperatures where you might lose different parts of the tree (flower buds, blossoms, green fruit, ripe fruit).

Will Buffalograss Grow in the Mojave Desert?

Q. Will Buffalograss grow in the desert?

A. Buffalograss grows perfectly well in the Mojave desert. The major problem is finding a source for it. I would not start it from seed if you want a good quality lawn. The best method would be to use sod but without a source of sod locally, you could have plugs shipped in from a reputable supplier.

Buffalograss can make a good quality lawn if you started from sod or plugs but not from seed..

Buffalograss is native to our dry grasslands and prairies of the United States. Like Bermudagrass and zoysia grass, it is a warm season grass which means it will become dormant or go to sleep during the winter months. It is best planted when soil temperatures have begun to warm in the spring or very early summer.

Preparation of the soil is very important for good establishment. Plugs are normally at least 2 inches in diameter and spaced 12 to 24 inches apart in the lawn area. Because Buffalo grass is a sod forming grass it fills the bare soil between plugs with stolons or surface runners. With good management the lawn area should be completely filled before it gets cold in the fall.

This is a bit controversial but research in Arizona has demonstrated Buffalo grass to use about the same amount of water as Bermuda grass but it does not require the fertilizer or the same level of management.

A reputable supplier out of Nebraska is Todd Valley Farms. Give them a call and talk to them if you are thinking about Buffalo grass.

Can I Grow Persimmon From Seed?

Q. I had a couple of persimmons from a friend's tree in California. Can I plant these seeds from this fruit and if so do the trees thrive here?

A. Yes, persimmons will grow in the desert with a little bit of extra care. Our desert soils must be amended with compost before planting. After planting, persimmons will perform best with a surface mulch of 3 to 4 inches of wood chips. Persimmons perform very well if you fertilize with compost once a year.

Persimmon leaf size with organic fertilizers like compost applied to our desert soils.

You can grow persimmon from seed easily but these trees will not be exactly the same plant as your friend’s. A tree from these seeds might have better fruit or the fruit might be worse.

To germinate, persimmon seed must go through about two months of cold, wet conditions,Similar to the conditions it would find in nature. In nature the fruit matures in late fall or early winter and drops to the ground in a layer of natural surface mulch or debris. In this surface mulch it spends the cold winter. In its native environment this surface mulch would stay relatively moist compared to our dry desert winters. 

Hachiya persimmon grown in the desert that is nearly mature. At this stage the seeds can be harvested but the fruit will not be quite at its peak of ripeness and will still be astringent.

You can simulate this by using a refrigerator. Refrigerator temperature is fine but the seed should be kept moist but not wet. These conditions remove inhibitors in the seed coat that may keep it from germinating. Make sure the seed is clean and pack them in ever-so moist sand before putting them in the fridge. This should not be in plastic bags but something that can "breathe" while in storage. You need to moisten the seed's environment periodically.

After the two months and freezing temperatures have passed, you can plant these seeds directly into amended soil in the garden area or in a container.

Alternatively, plant them directly into amended soil in the garden or container, moisten the soil, mulch it with 2 inches of wood mulch and water about once every 3 weeks during the winter. They should germinate in the spring in the spot where you planted them when the weather warms.

Saving Bougainvillea From Freeze Damage

Bougainvillea summer time

Q. While most of our bougainvillea are in large pots which we bring indoors for the winter, this year we planted one in an above ground planter built around the Jacuzzi. What should I do to help it survive the winter without having to dig it up and transplant it again in the spring?

A. Your bougainvillea will have a better chance of surviving the winter planted in the ground than it will planted in a container. However, expect it to be damaged this winter unless you are willing to apply heat to the area where it is planted and cover the plant all the way to the ground.

Bougainvillea that has frozen back during winter

If left unprotected, your bougainvillea will freeze to the ground as soon as temperatures drop below freezing. If temperatures dip quickly below freezing and rise above freezing in a short period of time, damage will be light. If temperatures dip below freezing and stay there for a while, the entire top of the plant above ground is likely to freeze and die.

The death of the top of the plant is not necessarily a big problem. The dead parts can be pruned back close to the ground and encouraged to regrow in the spring. My major concern is protecting the base of the bougainvillea, near the soil, so it can regrow.

Some inexpensive insurance is to pile several inches of mulch around the base of the plant just before it freezes. This wood mulch acts as an insulator which protects wood at the base of the plant from dying. Of course if temperatures get unusually cold for long periods, it is possible to lose the entire plant. But in most winters this will not happen if mulch is used.

In mid-March prune out any damaged plant parts back to healthy wood. Fertilize the plant with a high nitrogen fertilizer and water deeply. After it has re-grown significantly, apply a phosphorus fertilizer either to the soil or spray and liquid on to the foliage.

Protecting Plants from Freezing Weather