The New Year brought along good cheer and bitter cold temperatures across the California, Arizona and Nevada desert floor. We had rain followed by wind and cold. Temps in the Phoenix area dipped into the upper 20s and many of us are left with a yard full of frost burned palms, crunchy lantana and frozen bougainvillea. I’m here to tell you it isn’t as bad as it looks! Here are some tips on how to fix frost damaged desert plants.
The lantana (front) sage bush (right) and pygmy date palm (center) all have frost damage, which will be trimmed away in late February.
Plant Help For Frost Damaged Desert Shrubs
Let’s get the bad news out of the way. If you’ve planted anything in the past 12 months and it looks dead, it just might be. It didn’t have a lot of time to develop deep roots so be prepared to replace it. HOWEVER…wait until the end of March before you pull it out, as it could possibly grow back. Read below.
For established trees and plants, chances are the majority of what looks bad will come right back once it warms up. While a plant such as a lantana might be cold hardy to around 30 degrees, the roots themselves can take much colder temps before they die off.
In a few weeks it will be safe to start hard pruning. By hard pruning I mean cut off all of the frost burned stems/branches/damaged parts. Some things you can even cut back to the ground. In a couple of weeks you will notice it starting to grow back and by the summertime you won’t even be able to tell we had a hard winter.
I cannot stress enough the importance of waiting a little longer to trim these things. If we get a cold snap in early February and the frost comes again if you’ve hard pruned you could completely kill your desert plant. So play it safe and start cutting back around Valentine’s Day.
Here are a few more specific pointers for how to fix frost damaged desert plants:
These probably don’t look so hot right now. All of the bougainvillea in my yard look like someone put them in the freezer. The roots of a bougainvillea are frail but extensive. Cut off all damaged canes or any branches that have all the leaves killed off. If the entire plant looks frozen, trim it like you would a rose bush. Trim all the peripheral branches/twigs off and leave a few larger branches. It will grow back very quickly once it warms up, but be very careful NOT to trim back anywhere that looks like it is growing/unharmed. You want to keep as much of the living stems as possible.
Typically established hibiscus are pretty hardy but every once in a while the cold snap will cause your plant to lose its leaves. Trim this only to shape. It will start to grow back around early April.
Frost tends to turn parts of the sage bushes brown. The leaves will drop. You can selectively trim off the frost burned branches, otherwise just trim to shape.
It is often said you can’t kill a lantana! While this isn’t completely true lantana will most likely return. Every late winter I cut all of our lantana back to a couple of inches off the ground. This may seem harsh but believe me, they will grow back. This is called a ‘hard prune’. Hard pruning your lantana will also allow it to grow in thick and full, eliminating that leggy look lantana often develop.
The poor, poor ficus in the desert! It seems these big, marvelous guys just can’t get a break. Frost will burn the ficus in patches, you’ll notice a big patch of brown, dead leaves while the rest of the tree looks untouched. You can trim off the dead or just wait for the old leaves to drop off. Once the dead stuff drops you’ll have an easier time seeing which parts of the tree were damaged/dead and which parts are thriving. Trim off the dead and leave the rest alone, it will recover. Sometimes they will even lose every single leaf and start growing from out of the ground again.
If your cactus is damaged from the frost the tip or sides will turn from green to purple or black. If it’s purple, leave it alone. Chances are it will come back. If it is black, chop off the tip where it’s black. Yes, I am telling you to decapitate your cactus. The black means it is dead in that part and if you do not remove the dead it will rot and eventually kill the entire cactus. Chop off the black and in a few months it will start to sprout a few new pups off the chopped part, leaving you with a unique looking specimen. Do this on a warm, sunny day, the later in the season the better. If the cactus is jointed (like cholla, prickly pear, etc) you can cut at the joint as much as you need.
Agave and Aloe
Remove any wilted arms/leaflets about an inch from the center of the plant. It will harden up around the cut part and continue growing on its merry little way.
These probably have turned into straw. Hard prune down to about 4 inches. They will grow back fuller and healthier than the year before.
Yellow Bells, Honeysuckle, Bird of Paradise and Orange Bells
These two are semi-dormant during the winter anyway, you can remove the frost bitten stems and prune to shape. If it’s really damaged, cut it back to about a foot from the ground.
If you have frost damage on oleander you really got hit hard, because they are usually the last to show signs of damage. Remove the dead/damaged parts and prune to shape. Always wear gloves, as all parts of the oleander are poisonous!
If the bud of the palm tree is healthy then your palm is fine. Cut off the dead frond or the damage only, do not cut more than you absolutely have to. Palms need these green fronds to photosynthesize, which gives them the ingredients they need to be healthy.
Remember don’t start hard pruning until after Valentine’s Day, so save this list for mid-February and keep your chin up!