Weather Changes Everything By Staff Writer Stacey Warde.
Finally, after three of the hottest days on record, the heat wave broke, but not before nearly 200 of our blueberry plants had succumbed to the hot dry winds and baking sun. They were wilted, scorched and burned.
For three harrowing days of futilely fending off temperatures hot enough to literally cook the plants in their five-gallon grow bags, I was in a panic.
Nine rows—the upper south-facing part of the field that gets the most sun—were scalded so badly their leaves began to curl and turn crispy brown. I kick myself for having let them get so dried out that they began a kind of die back, but I don’t know what else I could have done.
On Monday, when downtown Los Angeles marked its hottest day on record at 113, a hot easterly wind blew hard at the farm like a blast from the furnace, toppling over some of the plants, and drying out their tender leaves. The sun also beat down hard, cooking the clay ground, and drying out the roots inside the grow bags.
Had I not watered in time, they would have literally fried.
Even after the heat wave had clearly broken, temperatures were still climbing into the 90s and the blueberry plants, half of which were bearing beautiful white blossoms for a late fall harvest, were still showing signs of stress.
I think we’re in the clear now, but there was plenty of damage, enough to plan a better strategy for coping with extreme weather. The 5-gallon grow bags, convenient as they are, don’t hold moisture for long when the temperature gets above 100.
Meanwhile, I’m nursing the plants the best I can, trimming away the heat damaged leaves and twigs, going easy on nutrients, and making sure they’re getting enough water.
Amazingly, with a little care, the blueberry plants seem to be responding well, doing what they do best, putting out new growth and blossoms. Although, the field appears like someone took a blowtorch to the tops of the plants, overall they’re showing good health and resilience.
Still, it amazes me how quickly weather can place sudden new demands on a farming operation. Just when you think things are running along smoothly—getting into a rhythm of irrigating and pulling weeds, for example—the temperature can run up or down so quickly that you’re cooked before you know what hits you.
When weather becomes extreme, everything else comes to a stop. The urgent need to protect the plants becomes paramount; forget the weeds, pests and feeding worries. Save the plants.
Saturday was the first really warm day, and I didn’t think much of it, when by noon the gauge had reached 100. I ran the irrigation and walked the field, as usual, looking for plugged or broken emitters, part of my daily morning routine.
Lately, even before the heat wave hit, I’ve found several plants that had completely dried up, not dead but the leaves were completely wilted and browning. I try to avoid this unwanted stressing of the plants by walking the field as I water, looking for telltale signs of broken connectors, plugged emitters and dried out bags.
Usually, when an emitter, which releases an average of five gallons per hour under the best conditions, is broken or plugged, it takes a couple of days for the plant to show the effects. Lately, in this heat, it takes only a day or less for a plant without water to wilt and turn crispy.
The easiest way to tell if a plant isn’t getting water is to look at the bottom of the bag. After 15 minutes of running, the water will begin to seep through the bottom and form a wet circle on the weed mat below the bag.
Another way to tell if there’s a problem with water is to look at the new growth. I’ve also been finding a lot of plants with their tender vibrant green shoots hanging limply at the tips—before it got hot.
Sunday was another hot day when the mercury rose above 100 before lunch. I knew that much more of this heat and we’d be in trouble.
Sure enough, on Monday, the whole field appeared wilted when I arrived at the farm; the temperature was scorching, and the dry winds sucked out what little moisture remained in the atmosphere. By noon, the temperature gauge had passed 104 in the shade and would soon reach close to 110.
With only 40 pounds of water pressure, I could run two, maybe three, of the eight valves at once. Eight valves run the entire irrigation system, covering all 1,500 plants. I usually run two valves at a time, watering roughly 320 or more plants at a time, on normal days.
In the heat, I tried to run as many valves at once as possible, knowing that the longer the plants went without moisture, the more likely they would suffer. But, without adequate pressure, which usually occurs when other areas of the farm are also being irrigated, it was mostly a hopeless task.
I ran the three lower valves first and for as long as possible, hoping to saturate the bags, before moving on to the next sections. The scorching wind, as much as the heat and sun, I knew, would quickly dry out the plants.
By the time I got to the upper end of the field, it was too late for the remaining nine rows of plants. They’d clearly dried out, the top leaves had in a short period of time turned brown and crispy.
It was heart wrenching, like taking a punch to the gut. There wasn’t much else to do but hope that the high-pressure weather system, which pushes out the marine influences we depend on here, would break soon. A few more days like this, and we’d have been finished.
I’m afraid that the 5-gallon bags have gotten too small for the thriving plants, which have grown nearly four feet tall and have bushed out into a thick green mass of leaves. The extensive leaf surface alone, which will transpire significant amounts of moisture, puts an incredible demand on water. Additionally, the roots have begun to fill the bags and suck up moisture much more quickly now than when the plants were smaller.
During a heat wave like the one we just experienced, this combination can spell disaster. We came perilously close to losing our field to the extremes of weather.
The only way I know to avoid the risk of burning or freezing is to get the plants into the ground. But that’s not going to happen any time soon, at least not until we can find a location suitable to our needs.
The problem with placing blueberry plants into the ground here is that the soil on the Central Coast is just the opposite of what they require. Blueberries like highly acidic, loamy soil. We’ve got highly alkaline and heavy clay soils. According to the experts, it can take up to one year or more to adequately prepare the soil for planting.
Until then, I’m going to recommend that we start transplanting the blueberries into larger containers. §