Stand Alone Pages

Saturday, May 9, 2020

Japanese Blueberry Growing Problems in the Desert

Q. We have three Japanese Blueberry in our yard; two in the backyard and one in the front. All three have dead branches yet there are scattered green leaves above them. There are far more green leaves at the bottom of the three plants. Is it possible this is due to a lack of water?

A. Japanese blueberry is not a good choice for a desert climate and soils but will handle it if planted in the right location, good soil prep and regular watering. If planted in a hot microclimate with alot of reflected heat and light it gets sunburn easily and dieback.

https://xtremehorticulture.blogspot.com/2015/07/more-problems-growing-japanese.html

Japanese blueberry is from Far Asia and not many deserts there so it is not really a desert plant.It grows better in a Mediterranean climate like you find in coastal CA. It grows better in a Mediterranean climate like you find in coastal CA. When grown there it is much easier to manage.

What To Do

So if the soil is covered in rock, if the water amount is not increased as the plant gets bigger then chances are good there will be problems.  Not sure what the reason is for dead branches but most likely related to soil management (not covering the soil in woodchips and not amending the soil so its more like soils in the Far East) or water or both.

Borers

It is possible to be a borer problem but I would need more information. Remove dead branches. Improve the soil and apply water to a larger area under the plant.

Orange or Yellow Bottom Palm Fronds Signal Removal Time


Q. The bottom layer of palm fronds turned an orange - yellow color almost overnight. Is this from too much water or not enough water?
Color change if the fronds of this Canary Island palm signals the owner to remove them.

A. Neither, the cause of it turning orange or yellow is natural. These orange and yellow colors are natural, masked by the strong green color that the chlorophyll provides. We see the same color changes in leaves in the fall color of trees.
            The bottom layer of fronds die a natural death. As these lower fronds approach death due to old age and shade, some of the minerals in the leaves are absorbed back into the palm, first turning the lower fronds orange or yellow and eventually brown. Sometimes these color changes occur quickly and other times more slowly.
            The nitrogen, phosphorus and potassium move out of the frond first followed by magnesium, chlorine, zinc and molybdenum. Lesser mobile nutrients are left behind which include sulfur, iron, boron, and copper. These would be the dominant minerals remaining if these palm fronds were used to make compost. This color change is your signal to cut and remove palm fronds.

Thursday, May 7, 2020

Pruning Standard Fruit Trees to Control Height?

Q. I watched your pruning videos on YouTube and learned a lot! Is it possible to reduce the size of a standard sized apple tree to a dwarf size this way?

A. Probably not. Standard sized apple trees may grow to 35 or 40 feet in height. You might be able to keep a standard sized tree under 20 feet tall (maybe 15 feet if you’re really aggressive) through pruning but I don’t think you will get it to eight feet tall which is what I aim for in pruning semi dwarf trees for backyards. I call the size of these fruit trees “ladder less”. The standard sized apple tree is just too vigorous for pruning to short heights.

Standard Sized Apple Tree Is Big

            Standard sized apple trees normally grow 30 to 40 feet tall. Buying these trees on semi dwarfing rootstocks will keep them smaller than this but it depends on which semi dwarfing rootstock the tree has been grafted onto. I have found that the M111 semi-dwarfing apple rootstock is probably the best semi-dwarfing apple rootstock for backyards in our climate.
            Using this semi-dwarfing rootstock, I have been able to keep Pink Lady and Mutsu apples, for instance, pruned at eight feet through appropriate pruning methods. Apple trees grafted onto M111 rootstock will normally get to 80% of its mature height if left unpruned.
            Nurseries sell fruit trees with a tag that calls the tree a “semi dwarf” because most people don’t know the different kinds of semi dwarfing rootstocks. In our area an apple that is labeled as semi dwarf is most likely grafted on to M111 rootstock. 

There are online stores for fruit trees, such as Grow Organic and Bay Laurel, that specify the rootstock used and the most common semi-dwarfing rootstock available on apples for backyards in the Western US is M111.

How Much to Water?

Q.. I am writing you to find out how often should I be watering my trees and shrubs. The weather got hot so quickly that I’m really not sure when to water. I have a California Pepper Tree, 2 palm trees (a canary date and a Mediterranean fan ) and 5 Japanese boxwood shrubs.  Any help you can give me is appreciated .

A. There are two questions that need answering: how many minutes to water each time and secondly how often.

https://wateruseitwisely.com/100-ways-to-conserve/landscape-watering-guide/plant/
The number of gallons of water given to a plant depends on its size; small trees are watered 18 inches deep, medium-size trees 24 inches deep and large trees 36 inches deep.

Establishing the Number of Minutes

The number of minutes depends on the soil you have and how big the tree is. Small trees are watered 18 inches deep. Medium-size trees are watered 24 inches deep. Large trees are watered 36 inches deep. Always apply the water to wet the soil at least half of the area under the tree's canopy. Small trees are less than 20 feet tall. Medium-size trees are 20 to 35 feet tall. Large trees are above 35 feet tall.

Your soil and how big the tree is so I can tell you the number of minutes. You have to figure that out for yourself. To do that I use a 3/8 inch diameter rebar 4 feet long. If the water didn't go deep enough, water more minutes until you get there.

A 4 foot length of three-eighths inch rebar I use for measuring how deep water penetrates in the soil after an irrigation.
Right after I irrigate I push this rebar into the soil in three locations, where the soil is wet, as deep as I can. The rebar pushes in easily if the soil is wet. When the water doesn't go any deeper and the soil isn't wet anymore it's hard to push.

Watering How Many Times A Week

Each time I water I use the number of minutes it takes to get the water to that depth. That doesn't change. What changes is how many times I water each week. This is for non-desert plants.For desert plants water less often but give them the same amount of water as I mentioned above.

Winter months every 10 days or more
Starting February 1 every seven days
About mid April twice a week
About June 1 three times a week

In the wintertime I water to that depth about every 10 days or longer. About February 1 I start watering once a week. Around the middle of April I water twice a week. Around 1 June I start watering three times a week. If it gets really hot I might water four times a week. A 3 to 4 inch layer of woodchips or rock helps keep the soil wet. I only use rock with trees that come from the Southwest deserts. All the rest of the trees I use woodchips.

By the way, none of the plants you mentioned in your question are desert plants.