Desert Horticulture Podcast: Bosc pear, winter irrigations, water softener and lemon bottlebrush

This episode discusses how to get Bosc pears to produce more fruit when a pollenizer tree is not close by. Bob Morris also talks about knowing when to irrigate fruit trees using the "old farmer technique" and as well as using new technology like soil moisture sensors and a piece of rebar. Everybody knows that water softeners are the bane of landscape plants if you're not careful. Learn some techniques that might save some landscape plants from dreadful water "softenitis". Lastly, lemon bottlebrush sometimes has yellow leaves and it's not because it's a lemon bottlebrush. Learn how to correct this problem and what causes it. All this on Desert Horticulture.

Is Organic Worth It?

Personally, I am beginning to question the value of organic production whether it is done in the United States, Europe, Canada, Australia or the Far East. In years past, when organic production was first starting out, I thought it was a great idea and a chance for the small farmer, particularly the local one, to compete in the food marketplace. 

I started having my doubts perhaps starting about 5 – 7 years ago for a variety of reasons. However, I still consider myself an advocate for locally produced food and getting to know your farmer as well as Good Agricultural Practices (GAPs), beginning with Eurepgap and more recently Globalgap.

Good agricultural Practices focus on a holistic, and in my opinion, a more rational approach toward producing food by small farms. But still, large scale conventional farming will never replace the "local producer". 

I hope you enjoy reading this article from Chemistry World.

Read the article here.

Fertilizer Injectors, Potting soil vs Garden soil, and Santa Rosa Plum Podcast

Join Bob Morris on his podcast talking about why you should or should not use a fertilizer injector, the difference between a potting soil and garden soil and why Santa Rosa plum might be a good fruit tree to have.

Non Myers Lemon and Picking vs Flowering

Q. My lemon is not a Meyers lemon but the tree is starting to flower. I didn’t want to pick them this early because they are still getting sweeter. Does the "remove lemons before the tree flowers" rule apply to this variety as well?

A. Yes it does. It applies to all fruit trees. Try thinking like a lemon tree. The reason the tree produces fruit is to reproduce. When the fruit drops to the ground, the fruit rots and releases nutrients that feed developing seedlings.

Eureka lemon growing in Las Vegas

            The tree “knows” if there is fruit attached to its branches or not. It can’t see anything but there are other types of communication that trees have perfected. When the fruit has been picked, the tree “knows” the fruit is no longer there.

            The reason for picking fruit before the tree begins flowering is to send “signals” back to the tree that it no longer has fruit attached to its branches. When fruit is missing, the reproductive or flowering cycle of the tree is encouraged.

            The beginning of flowering is the beginning of the reproductive cycle. The normal flowering cycle of trees is at certain times of the year. If this time for the normal flowering cycle to begin has passed or is delayed, the tree may not flower at all or flower very lightly.

            You are right. Most citrus are considered non-climacteric, or, in other words the fruit doesn’t increase in sweetness after it is picked. It is best to wait when picking lemons to improve its sweetness, but you don’t want to leave it on the tree long enough to interfere with flowering.

            Other fruit which don’t ripen or ripen little after picking include figs, grapes, pomegranates, cherries and apples. As a consumer this means the sweetness of non-climacteric fruit does not increase much, if at all, after picking.

           If citrus is left too long on the tree fruit quality is reduced because it becomes “pithy”; it starts drying out. Remove all fruit from trees before they begin their next flowering cycle.

Store Bought Lemon Better than Mine

Q. I found a Myers lemon at a store in California that looked much different than my Myers lemon; they were smaller, darker orange and seemed sweeter to me. Is this Myers lemon different from mine? 

A. There are differences between fruit grown in one geographic location versus another geographic location. Sometimes we call these location differences “agroclimatic regions”.

Both were labeled as Myers Lemon. The one on the right was bought in the store.

            Agroclimatic regions include differences in weather but also differences in soils. All these “differences” evoke changes in fruit quality, reflected in the quality attributes of the fruit. How the plant is managed or manipulated also creates changes in fruit quality.

            We see these agroclimatic differences in vegetables and ornamental plants as well. Sometimes these differences are good and sometimes they are not. We don’t know until we grow these plants in different locations.

            Fruit grown in the Mojave Desert does not have the same quality attributes as fruit grown in non-desert areas. There are many reasons for differences in ‘sweetness’, color and sugar content in fruit.

            Sweetness or sugar content can be masked by the amount of acidity the fruit has. Fruit grown in the desert typically has high sugar content and lower acidity, so some desert grown fruit may taste bland compared to fruit grown in non-desert climates. Other fruit might be better.

            Differences in fruit quality can be attributed to plant differences, agroclimatic regions, how the fruit is managed on the tree or after it is picked. Differences in fruit quality can be from the variety or plant selection, graftage, fruit maturity, climate and weather, plant nutrition, age of the tree, how much fruit is grown on the tree, and others.

            Try fertilizing the trees with a good “citrus” fertilizer or compost. Change the amount of water the tree gets and try harvesting the fruit later or earlier. Minimize the length of time the fruit is kept in storage once it is picked and off the tree. Prolonged storage can reduce sugar content.

Watering Plants with Water from a Water Softener? No No No

Q. We have a vegetable garden and an ornamental garden.  We didn’t think about it, but we just installed a water softener.  This softened water also comes out of the garden hoses.  Is this water bad for our plants?

A. Yes it will be a problem if you water with sodium-based salts from the water softener in it. Sodium is toxic to plants. This inexpensive salt used in water softeners also contains chlorine which is also toxic to plants. A double whammy.

            You have three options. The first is to run a new water line and hose bib from a point upstream of the water softener and use this water for irrigating. Secondly, install a hose bib from the irrigation line used for the garden since the water supply for outside irrigation is connected before the water softener.

            The third option is to use potassium-based water softening salts rather than sodium-based salts. These water softener salts are more expensive but less damaging and will still soften the water. You’ll find this type of salt for water softeners anywhere that sells water softener salt.

Irrigating Fruit Trees in the Winter Depends

Q.  How often do deciduous fruit trees, in this case a Blenheim apricot, need to be watered during the dormant season?

A. It's hard to give a blanket recommendation about how often to water because of the differences in soil, root growth and if people are using a surface mulch or not. Because of these differences, how often to irrigate might vary a couple of days either way.

            The best way is to use a moisture sensor such as those inexpensive houseplant moisture sensors. Insert the tip in the soil about 6 inches deep and irrigate when the meter is around 6. You should be at able to water no sooner than every 7 days and maybe every 10 days depending upon your conditions.

Soil moisture sensor with 24 inch stem

            But if the tree is surrounded by dry soil it may be closer to 7 days. If the tree is surrounded by other trees that are irrigated, it might be 10 days. And if you have the soil covered in 3 or 4 inches of woodchips you can extend it perhaps an extra 2 days. That's my best guess.

            But you are better off using a moisture sensor to get it more accurate than this. To determine the number of minutes to irrigate, I use a long probe like three-eighths inch rebar and push it into the soil after an irrigation. It's hard to push it deeper if the soil is dry beneath where you water. Recently at one of my classes, someone mentioned they are using a wooden dowel to do the same thing.

Soil moisture sensor meter reading "0" or dry.

            I just push it down until it's hard to push any further and that tells me how deeply I've irrigated. With fruit trees I like to irrigate 12 to 18 inches deep. 

Bosc Pear Needs Bartlett Tree as Pollenizer

Q. I planted a Bosc pear tree seven years ago not realizing it required a second pollenizer pear tree.  For several years I did get a few pears even though the tree had lots of flowers. I think my neighbor’ s pear tree was the pollenizer, but it seems to be failing. I have no room to plant a pollenizer pear tree. Not sure what to do.  

A. I have grown Bosc, Anjou and Bartlett here in the Mojave Desert in the past and noticed, the same as you, the fruit set wasn't great in the Bosc and Anjou compared to the Bartlett. It is possible it might be a humidity problem, like our problems with sweet cherry and Hachiya persimmon growing and setting fruit in our climate.

Bosc pear producing immature fruit in the Las Vegas valley

            Bartlett and Red Bartlett seem to set fruit better in the desert, compared to Bosc and Anjou when there is plenty of flowers and honeybee activity. Keep that in the back of your mind.

Bartlett pears produced in the Las Vegas valley.

            Since Bosc needs a pollenizer tree, you will have problems producing  fruit if there is no other European Pear flowering at that time. It might be possible to buy a Bartlett and plant it on the south side of that tree, 18 inches away, and prune out some limbs to make room for it. In other words, integrate another pear that flowers at the same time and see if that helps with the fruit set of your Bosc pear. Bartlett is a good pollenizer for Bosc.

Sensation Red Bartlett producing fruit in the Las Vegas valley.

            Make sure you have rosemary or other winter blooming herbs to attract honeybees to the backyard that time of year. Anything that blooms during the spring months and attracts bees will work. Because pear blooms a little bit later than some other fruit trees, you might also consider attracting leaf cutter bees as pollinators to your yard.

Comice pear fruit in the Las Vegas valley.

            Try putting a small birdbath or shallow water source and that will attract honeybees as well. When it’s warm, honeybees Hall water back to their colony. Put rocks in the birdbath so that honeybees have a place to land and retrieve water.

Nesting blocks for leafcutter bees

            If you can synchronize the blooming of these two pear trees, and you still don't get fruit set on the Bosc pear, you can assume it's a humidity issue. If it still doesn’t set fruit, get rid of the Bosc and at least you can have a Bartlett. I would look closely at Red Bartlett if you want the red color but both Bartlett varieties work here.