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Have you ever had a sunburn?  Maybe a better question is, “Who hasn’t?”  

Well, did you know that many plants get too much as well?

I recently made a house call for a client who was worried about her newly planted citrus trees.

new citrus trees planted in pots.

Sunburned Citrus

This particular client has a large courtyard with several new citrus trees in pots.

The citrus were planted in spring and as summer progressed, the client noticed the leaves on her orange tree turning yellow.

sunburned citrus

Now yellow leaves can indicate a number of different problems.  But in this case, the diagnosis was rather simple – her citrus tree has a case of sunburn.

Here are some common signs of sunburned plants:

– The areas of the leaf that are yellow are in the center and NOT along the tips or edges.

– Often, the yellow areas begin to turn brown.

– Signs normally occur in the summer months.

– The sunburned leaves are usually located on the south and west-facing parts of the plant.

– This particular citrus tree is in an area that receives reflected, afternoon sun.

So, what can you do to prevent sunburned citrus?

In this case, the solution is simple – moving the citrus tree to another part of the courtyard that receives afternoon shade is all that is needed to prevent further sunburn damage. OR, 50% shade cloth can be used from mid-May through September.

Citrus do best when planted at least 10 – 15 ft. away from walls, which absorb the heat of the day and re-radiate it out.

Avoid planting where they get the full force of afternoon sun.

Roses Feeling The Heat

Photo: Roses Feeling The Heat , My Abraham Darby shrub rose and my little dog, Tobey.

If you live in a hot arid climate, chances are that your roses are feeling the heat and aren’t looking their best right now. While gardeners in cooler climates celebrate summer with beautiful rose blooms, the opposite is true for those of us who live in the desert.

Surprisingly, roses actually grow quite well in hot, southwestern zones, and even though mine look somewhat sunburned – I’m not worried because this is normal.  

You see, roses that are grown in the low desert regions, don’t like the intense sun and heat that summer brings. As a result, the flowers become smaller, and the petals burn in the sun and turn crispy.  By July, you are unlikely to see any new roses appearing until Fall.

Roses Feeling The Heat

The rose blooms aren’t the only parts of the roses affected by the summer heat – the leaves can become sunburn.  

The sight of brown crispy petals and leaves may make you want to prune them away, but don’t.    

Why?

Pruning will stimulate new growth that will be even more susceptible to sunburn damage.  Second, the older branches and leaves will help to shade the growth underneath the sun.  

I know that it is very hard not to prune away the brown leaves – I feel you. However, in September, pull out your pruning shears and prune back your rose bushes by 1/3. This removes the sun-damaged flowers and leaves, and stimulates new growth. 

Roses Feeling The Heat

If you lament the less than stellar appearance of your summer roses and feel that it’s easier to grow roses in other climates, you would be wrong. 

Oh, certainly, we have to deal with our roses not looking great in the summer.  But, compare that with gardeners in other regions who have to deal with the dreaded Japanese beetle that shows up every summer and eats their roses. Or, people who live in more humid climates and are having to deal with severe cases of blackspot or powdery mildew (white spots on the leaves).    

Lastly – we are fortunate to enjoy two separate bloom seasons for our roses.  In fall, when many other gardeners are putting their roses to bed for the winter, ours are getting ready to bloom a second time that year.

Roses Feeling The Heat

And so, I will ignore my less than beautiful roses this summer, because I know that they will look fantastic this fall 🙂

Two New Roses Find a Home in a Desert Garden

Protect Citrus Trees From a Heatwave

Living in the desert southwest, I am blessed to be able to grow a variety of citrus trees in my garden and they do very well under most circumstances.

However, when temperatures outside of the average highs and lows occur, steps need to be taken to protect them. With this week’s record-breaking highs, my orange tree has been suffering as is evident from its sunburned leaves. So I thought, this is a great opportunity to talk about how to protect citrus trees from a heatwave.

Protect Citrus Trees From a Heatwave

1. Provide temporary shade 

The west and south-facing sides of citrus trees are susceptible to sunburn during a heatwave. This shows up as yellowing or browning on the leaves on those sides of the tree. Sunburn can also occur on immature citrus fruit, so it’s important to protect them.

While spraying citrus trees with sunscreen isn’t an option, adding temporary shade is. Put a large piece of burlap over the tree, focusing on those south and west-facing exposures. Burlap is inexpensive and does allow some sun to penetrate, which is important. You can purchase burlap at your big box store, nursery, or Amazon (affiliate link below).

Burlapper Burlap Garden Fabric (40″ x 15′, Natural)

You can use a bed sheet in place of burlap for temporary shade. Another option would be to place a shade tent/canopy to help block the sun’s westerly rays.

Shade cloth is very useful as a sun shield when placed on a scaffold or other support – it’s important not to rest it directly on the tree as it gets hot and can burn the leaves.

Protect Citrus Trees From a Heatwave

2. Increase irrigation and water early in the morning

When temperatures soar above normal, citrus trees, like most plants, lose more water through their leaves. As a result, their regular watering schedule isn’t enough to meet their needs, so increase the frequency of watering as long as the heat wave lasts. 

When you water is vital as it is difficult for plants to uptake water in the middle of the day. This is because all of their resources are dedicated to enduring the stresses of the heat and it’s hard for them to divert those to uptake water. Water in the early morning, which will allow them to build up a water reserve that will help them through the day.

online-class-desert-gardening-101

Tired of struggling in the desert garden? Sign up for my online course, DESERT GARDENING 101.

Once the heat wave is over, remove the temporary shade and resume regular watering. By implementing these two methods, you’ll enable your citrus trees to weather brutal summer temperatures and minimize any negative effects.

*Sun protection for the trunk and bark of citrus trees is essential throughout the entire year. Here is a past blog post showing you how to shield these parts of your tree and why it is so important. 

Did you know that you can often tell what is wrong with a plant by looking at its leaves?

It’s true.

Diagnosing Common Plant Ailments

Photo: Manganese deficiency

‘Reading the leaves’ to diagnose common plant ailments isn’t hard to do if you know what symptoms to look for.

Problems such as iron or nitrogen deficiency are fairly easy to identify as is salt and sunburn damage.

Read on to learn how to diagnose these problems in your plants in my latest Houzz article:  

What’s Wrong With My Plant? Leaves Often Hold the Clues

Citrus Trees Need Sunscreen

Last week, I was visiting one of my favorite clients when I noticed that one of her citrus trees was showing signs of sunburn, which led to me explaining to her that even citrus trees need sunscreen to prevent sunburn in many cases.

Citrus Trees Need Sunscreen

You can see the lighter-colored bark and some cracks as well along the branch. It turns out that citrus trees are very susceptible to sunburn.

So, why is a sunburned citrus tree something to be worried about?

Well, when a tree becomes sunburned, it often forms cracks in the bark and within these cracks, damaging insects or fungus can find a nice home.  Frost damage can also cause cracks in the bark.

In recent years, I have had to deliver bad news to people whose citrus trees became infected with sooty canker, which is a fungal disease that affects the branches and trunks, which takes root underneath the cracked, flaky bark.

Citrus Trees Need Sunscreen

Several times, I have had to tell homeowners that their much-loved citrus tree was badly infected with sooty canker and had to be removed.  You can read more about the signs and treatment of sooty canker, here.

Thankfully, there are things we can do to reduce or eliminate the chance of sunburn to our citrus trees.

Citrus Trees Need Sunscreen

1. Allow citrus trees to grow their lower branches. They will help to shade the trunk.  A bonus for citrus trees grown this way is that the most fruit is produced on the lower branches that also tastes sweeter.

Citrus Trees Need Sunscreen

2. Protect exposed trunks and branches by using citrus paint (available at your local nursery) or by simply mixing white latex paint water so that the resulting mixture is 1/2 paint and 1/2 water. You can also purchase tree wraps made from burlap, which can also help to protect them. Avoid using oil-based paint.

However, if you allow the lower branches of your citrus tree to grow and the trunk is shaded, than you don’t have to paint them. 

citrus trees

3. Don’t over-prune your citrus trees.  The photo above, is an EXTREME example of what not to do.

Citrus trees should be pruned in March, and concentrated on removing dead, diseased or crossing branches.  Avoid pruning more then 20% of its foliage in any given year.  *Remember, that the leaves make food for the tree, which will in turn, produce delicious fruit. If pruning leaves you with exposed branches, then coat them with citrus paint.

**See how to protect citrus from the damaging effects of a heat wave – here.

Even Citrus Trees Need Sunscreen to Prevent Sunburn

I always wear sunscreen whenever I venture outdoors.  Years spent in California at the beach as a teenager, trying to tan my fair skin did not work.  Now, I try very hard to protect my skin from the desert sun.  I do however, often forget to wear my hat as it does mess up my hair 😉