Ripe for Controversy

Columns - Hort How-To

Are you deciding when to harvest based on misinformation?

Subscribe
Photo: Courtesy Otoké Horticulture

When you think of “ripeness,” you might think of western slope Colorado peaches dripping juice down your chin as you take a bite. Georgia folk would say the same, and that is the point: Most people have had a near-religious experience with a perfectly ripe piece of fruit.

Webster’s defines “ripe” along the lines of the condition of "being brought to full flavor or the best state." That is a pretty wide definition, but is it safe to say that size, color, texture, juiciness, aroma and taste are all attributes associated with our idea of “ripeness.”

The term “ripening” has also long been part of marijuana-cultivation practice. When a client ties its production harvest dates to the concept of ripening, decisions that impact the operation's production output and financial success are being controlled by that concept and are based on opinion and speculation.

Compared to all other inputs for cannabis cultivation, time is everything. The more time spent under the sun/lights, the more the product costs and the longer the period between harvests. The operation's total annual production is dependent not only on capacity, but also on the growth cycle. The difference between four and five turns through the flower rooms can be a few days of time spent waiting for “that perfect moment” to harvest.

Seasonal fruit growers may have the luxury of letting apples and peaches ripen a little longer if the weather allows, but more often than not, their market contracts contain a delivery date. Year-round growers, however, must keep crops moving, and delay cannot be tolerated. Any process that can be delayed by an individual’s opinion is not compatible with a schedule-based business model.

So if by “ripen,” a grower means the time frame where flower colas plump up quickly, or when a plant is flushed, we won’t quibble with that. We do, however, flinch if the grower follows someone’s eye and experience to set harvest dates. We will ask the grower to describe how they decide when to harvest plants.

The one common trait growers talk about and practice is looking at trichome color. It is common for growers to whip out an eye loupe and say they generally wait until 30 percent of the trichomes turn amber before they harvest. Unfortunately, what we do not get from them is an explanation of what the appearance of the trichomes means relative to the plant.

Better taste and smoking, higher potency and “different effects” are what growers tell us they have experienced from waiting until that “right” moment to harvest. What we have not heard is a viable description of the mechanism for rapid changes in flower chemistry.

Naturally, we are drawn to examine how a few days can dramatically change the plant’s chemistry after some 14 weeks of growing.

Tomatoes, Peaches and Cannabis

The ripening tomato or peach is quite unlike sinsemilla cannabis. Both the tomato and peach fruits are the result of pollination, and sinsemilla is the result of lack of pollination. The tomato and peach undergo dramatic changes as the reproductive tissues transform into the seed-containing endocarp and the meaty, juicy carbohydrate-storing pericarp. The biochemistry of fruit is complex.

By comparison, sinsemilla flower masses are pretty boring. The stem of a denuded bud shows us that in the reproductive phase the plant does not change much from vegetative growth, except that intermodal distances grow progressively smaller, creating the tightly packed flower masses. The top of the cola is the apical growing point of that branch and, just as in veg, adds height, as the lower “branches” of the cola continue to lengthen and branch off, adding girth and mass.

In other words, the differences in this plant between veg and flower are not as significant as one might think.

The absence of pollination results in the lack of initiation of the complex types of chemistry the plant’s genetics have all coded up, ready to produce seeds. So while fruit also undergoes dramatic changes as it matures, with carbohydrates being turned into the familiar sweet sugar of fruit, color changes occur, stems weaken and the fruit falls.

None of those kinds of changes appear to be happening in cannabis. At least at the visible level.

While the cannabis plant does not undergo a ripening in the traditional sense, the question remains whether the plant chemistry is changing during the period leading up to harvest. Again, many believe that waiting for the “right” moment can produce differences in the taste, aroma, potency and smokeability.

For those, like us, who love the medical potential of this plant in particular, it would be a wonderful thing if we really could manipulate the chemical content of the plant through cultivation techniques. But chances are that the plant’s genetics control the chemistry, and cultivation controls the yield.

Genetic science tells us that a Black Krim heirloom tomato tastes the way it does mainly because of its genetics, its DNA. This is true of all foods. Black Angus seems to be “the” beef to eat these days, but when you get down to it, steak is steak, and other than controlling feed and maybe better curing, it is always, basically, steak — regardless of the cattle type.

So while the farmer/grower can somewhat modify flavors and textures through their growing and cultivation processes, the basic elements of taste and aroma are locked in plant seeds and animals.

Only the genetic change that occurs from breeding can change a plant’s hard-wiring. This makes it difficult to imagine that anything a grower can do could overcome that programming and force the plant chemistry to change dramatically in relatively short periods of time.

Growers need to focus on lab testing so that decisions are based on a measurable quantity, not opinion. Today, we can test plant chemistry throughout a plant’s lifetime and see how the characteristic terpenes, nutrients and cannabinoids change. That is the kind of data on which growers can base solid decisions.

If that information ends up indicating that the plant’s chemistry develops and stabilizes fairly early in flower, then there is nothing to wait for late in harvest, and the decision of how long to leave the plant in flower is reduced to an optimization of annual throughput.

About the Authors:Kerrie and Kurt Badertscher are co-owners of Otoké Horticulture LLC (OtokeHort.com), and authors of “Cannabis for Capitalists.” They have worked with large-scale cannabis producers for more than 5 years. Kerrie has been involved with plants her entire lifetime and earned certification as a Professional Horticulturalist by the 100-year-old American Society for Horticulture Sciences. Kurt brings his 34 years of corporate experience and operations management skills to bear on the business challenges of cannabis cultivation.