Given its subtropical location next to the Gulf of Mexico, and with the mighty Mississippi River running through it, you might think that growing hemp in Louisiana would be an easy affair. The temperate-hardy crop can thrive here, but it takes more than just planting some seeds and standing by waiting for magic to happen. There are several discrete, yet interrelated, agricultural factors that influence farming in this state.
Plant Hardiness Zone(s)
The first thing to consider when determining if hemp will grow in your part of the state is the plant hardiness zone of the region where your field will be located. Hemp is cold-hardy down through zones 8a-11b, which means it can tolerate cold temperatures down to the range of 10-50 degrees Fahrenheit.
The state of Louisiana does not experience freezes very often. The average number of annual days with temperatures at freezing or below range from less than 10 in the areas including New Orleans and its surrounds up through only 36 around Shreveport. In fact, anywhere in the vicinity of the mouth of the Mississippi River typically only experiences a freeze once every seven years or so.
From Shreveport to Ruston at the northern end of the state is an 8a zone, then transitions to 8b around the mid-state region. The coastal parishes are predominantly 9a and 9b with some small patches of 10a at the extreme southeast.
The subtropical, humid climate in Louisiana is not ideally suited for hemp growth due to the fact that humidity can cause diseases, mold and fungal growth. However, growing in the cooler fall, winter and spring months should prove more suitable. The high average rainfall that occurs all year round in Louisiana is also sub-optimal for hemp plants, which prefer 10 to 12 inches of rainwater per season.
All this precipitation does make for cooler seasons than might otherwise occur in the deep, hot south, and these conditions are more conducive to hemp’s success than dryer ones would be. To deal with the excess water, soils can be drained with special aerating equipment, although this may be unnecessary during seasons with below-average rainfall.
Length of Growing Season
Hemp usually takes 120 days to mature, and because Louisiana’s growing seasons are comparatively long next to most other states, farmers and growers furthest south need not be surprised if they pull of a double-harvest each year, seeing as they’ve got a good 300 days to do it. Mid-state Luisianans can still take heart with the average 220 days they’ll have to work with as well. Depending on the date of first freeze, even those in the state’s northern reaches could get that kind of output too if they play their cards right.
Average Annual Sunlight
The typical annual sunlight in Louisiana averages 2635 hours per year, just over 7 hours per day. More than 60 percent of daylight hours bring sunny weather, with the rest characterized by cloudy, hazy, shady, or partly-sunny skies.
Average Annual Precipitation
The average annual precipitation in Louisiana is roughly 50 to 65 inches of rainfall per annum, more than enough to help plants and vegetation to grow. Way more than enough most of the time. All that water tends to leach nutrients out of the soil, even down to the 12’’ burrowing depth of the hemp taproot.
With its mean elevation at a mere 100 feet or so above sea level, Lousiana also has one of the lowest high points among all 50 states. The highest point is in Bienville Parish, where Mount Driskill sits only 535 feet above sea level and roughly 230 feet over the surrounding terrain. Some places along the Delta dip even below sea level. While hemp tends to prefer elevations of at least 600 feet above sea level, this is often to do with common beneficial temperature and soil traits found at those altitudes.
Soil pH across Louisiana varies greatly due to the composition, but can be said to be mildly acidic as a general rule. Fertilizers will likely need to be employed to bring soil to its preferred 6.5-7.0 pH levels it likes best.
Testing is necessary to determine which of the 300+ soil varieties that could be present in your field(s). Louisiana soils are typically fertile, containing three different granule sizes, ranging from the smallest of clays up through silt to the largest particle types (typically sand). The endless possible combinations of these constituents creates a dozen different soil textures across the state. The fertile sedimentary deposits of the Mississippi Delta comprises ⅓ of all soil in the state. Northern soils sit on hilly terrain and are less sandy than southerly types, which are of a coastal marsh or bayou texture profile.
Be on the lookout for aphids, tomato hornworms, whiteflies, and imported fire ants, all known to be hemp pests. Also, watch out for chinch bugs, spittlebugs, plant bugs, leaf hoppers, and clover-head weevils.
Obtaining A Hemp Grower’s License In Louisiana
Under federal law, it is illegal to grow hemp anywhere in the United States without first obtaining a grower’s license from the appropriate regulatory body for the state in which the interested party intends to plant the crop. For information on the legal status of hemp in Louisiana, as well as a breakdown of the application process, click here. Read about hemp legality by state.