A Few More Words About Rainfall

Thirty years ago I had a neighbor who long ago had been a writer for The Miami News. In 1926, her boss gave her a plum assignment – the lead story in the women’s section of the issue for Sunday, September 19. The young reporter chose to write a piece about home remodeling, ordinarily an upbeat topic. But on the day before her story ran, Miami was hit by the unforgettable hurricane whose eye passed directly over the city. My neighbor was embarrassed by the fact that her advice on remodeling might seem to be trivializing the plight of storm victims, many of whom now lived in buildings left looking like dollhouses, sides ripped off for all to peek into.

This was clearly an instance of inadvertent bad timing, and last weekend there was a little bit of that on this website. While we were preparing an article with advice on how to deal with the drought, the skies opened up, and at Richard Lyons’ Nursery it rained hard two more times that day. And rain fell again the next several days! It appeared that our drought might be ending, but dry conditions have returned. This might be a good time, then, to take a little closer look at rainfall patterns in southern Florida, so that you might be better apprised of those times of year when you need to pay special attention to irrigation.

As mentioned last week, the rainy season in southern Florida comprises parts or all of six months. Rainfall patterns here are like those found in much of the Caribbean Basin, where traditionally dual peaks occur during the rainy season. In our region, for many years those peaks have been May-June and September-October. But something has changed over the past 35 years or so. Now the peaks are more closely spaced. The rainfall totals for June-July (16.17 in Miami, 16.14 in Ft. Lauderdale) and August-September (18.74 in Miami, 16.03 in Ft. Lauderdale) now exceed those of May-June and September-October.

But one thing has remained relatively constant: July is the driest of the months entirely within the rainy season, and that leads to a very stressful time for plants. According to the National Weather Service, normal rainfall this month is 6.50 in. in Miami and 5.98 in. in Ft. Lauderdale. That would be nearly record-breaking in a place like El Paso, Texas, but it is fairly light in a region where so many tropical ornamental plants are grown. The risk is that, even in a typical July, we often experi-ence a stretch of five days or so in which no rainfall occurs, and that can devastate containerized material. So homeowners must keep an eye peeled toward signs of drying in their special plants.

It is also important to know the rainfall patterns for the rest of the year, because the low rainfall and breezy conditions of the dry season also impose the need to monitor plants, whether inground or containerized, for moisture loss. Following is the complete list of National Weather Service monthly rainfall averages for Miami and Ft. Lauderdale, respectively, covering the period 1980-2010. Even though annual rainfall during that time actually increased over historical norms, to 61.15 in Miami and 62.18 in. in Ft. Lauderdale, the continued low levels of dry-season precipitation underscore the necessity for diligence in watering practices.

January                   1.62                  3.63

February                 2.25                   2.96

March                     2.25                   3.36

April                       3.14                   2.89

May                        5.34                   4.65

June                       9.67                  10.16

July                        6.50                    5.98

August                    8.88                    7.44

September              9.86                    8.59

October                  6.33                    6.82

November               3.27                    3.24

December               2.04                    2.46

Drought Calls for Special Measures

The rainy season in southern Florida is the time of year when precipitation comes not from cold fronts passing through the area, but from the combination of heat and moist air. It is generally considered to span the period between May 20 and mid-October, a time when dew points are consistently above 70°, an indicator of high humidity. After April’s rainfall exceeded the norm, locals might have expected an early start to the 2015 rainy season. But precipitation in May was less than half of normal, and we are now more than a month late for the true start of the wet season. Over many decades June has been the rainiest month in both Miami and Ft. Lauderdale — more recently, September, by a small margin, has become Miami’s rainiest month — but the drought has gotten a tighter grip during this unusual June. While homeowners might appreciate not having to mow the lawn as frequently, the parched conditions pose potentially serious problems in the landscape, requiring special care.

Many of the plants which we have in the ground are native to either tropical rain forests or regions which experience high seasonal rainfall. Accordingly, they not only are accustomed to receiving ample moisture during the hottest time of the year, but they may even have evolved to rely on a relatively small root system to capture soil moisture. As a result, when a drought develops, those plants are prone to suffering greatly. It is important for you to make sure that your inground landscaping is sufficiently hydrated. Frequent brief irrigation is not recommended. Instead, you should provide a thorough soaking. If you aren’t already mulching trees and shrubs, you should do so, making sure to leave an open area around the base of the plants to discourage insects from chewing on stems. The mulch will act to keep moisture in the ground, an especially good benefit on breezy days any time of year, but particularly during the winter. (Mulch also improves the soil as it breaks down, another compelling reason to use it as part of your maintenance practices.)

If you keep plants in containers, you will need to be even more vigilant. Good soil mixes are fast-draining in order to discourage disease, but during periods of drought, soil porosity may create a threat. Windy days can desiccate containerized rootballs within mere hours. Until we begin to receive consistent rainfall, you may need to water some of your containerized material on a daily basis.

Special care also needs to be taken when fertilizing. First, since drought-stricken plants may have stopped growing actively, you might be well-served to reduce the amount of fertilizer you apply, lest you overwhelm the plant. Second, be sure to irrigate the plant both before and after applying fertilizer in order to minimize the risk of burning roots or leaves. This recommendation holds even when recent weather conditions have been normal.

Barring the drought of the century, at some time this summer we’ll experience a lot of rain in a short period; that’s the tradition in our area. But until that happens, take some extra steps to give Mother Nature a hand.

Bad Outlook for Florida Citrus Gets Even Worse

On January 16 of this year we published the State of Florida’s updated, discouraging outlook for citrus production. Unfortunately, that pessimism has only deepened since then. State agriculture commissioner Adam Putnam, in a message distributed this week and reprinted below, reports that Florida’s orange harvest will be its lowest in 50 years. The cause is citrus greening, a disease for which a cure has not yet been developed.

And citrus is not the only important crop in peril in Florida. The avocado industry is under siege due to laurel wilt, which remains unabated in the southern part of the state. Accordingly, Richard Lyons’ Nursery will continue to decline selling either citrus or avocado trees until reliable, affordable treatments to prevent citrus greening and laurel wilt are developed.

Friend, Florida growers are expected to harvest the smallest orange crop in nearly 50 years, and all because of a tiny insect. Citrus greening, a bacterial disease spread by the Asian citrus psyllid, is an existential threat to Florida’s signature crop. In just 10 years, citrus greening has cut Florida’s annual citrus harvest by more than half. The health of Florida citrus is important to every Floridian – not just those who depend on it for their livelihoods. With a nearly 500,000 acre footprint in Florida, citrus has a profound impact on so many of our interior counties and the quality of life of the surrounding communities. However, hope is not lost. We are partnering with the industry, the federal government, universities and private companies to develop cutting-edge solutions. We will continue to fight to save Florida citrus, its more than $10.7 billion economic impact and the more than 64,000 jobs it supports. For more information on what we are doing to save Florida’s signature crop, visit FreshFromFlorida.com.



Adam Putnam

Florida Commissioner of Agriculture

Aristolochia (Dutchman’s Pipe or Pipe Vines)

Aristolochia, is a genus of woody vines commonly called, Dutchman’s Pipe or Pipe Vines.  This is due to the shape of the flower resembling a pipe in many species.  It is also called Calico Flower, because the pattern on the flower resembles calico fabric. Many butterfly enthusiasts in South Florida grow this vine for the larval food of the Polydamus Swallowtail(Battus polydamus), sometimes called the Gold Rimmed Butterfly.  A black butterfly with gold around the wings and no extended ‘tails’ on the hind wings.  It is the only eastern United States Swallowtail without tails. Richard Lyons’ Nursery has a few species of Aristolochias in 3gal. containers.