One Tent, Two CBD Packs

Put two packs of CBD seeds beside each other, one marked 1:1 and the other 20:1, and the two look identical: same breeder’s packaging, the same seed count, contents which nobody’s eye can separate apart. Grow them in the same tent and they go their separate ways from the first stage and never meet again. The cause is one single gene, and the easiest way to see what it does is to track the two packs along each stage both go through: the breeding that produced them, the seed, the seedling, the flower room, the harvest, the jar, the lab bench and the law. The lines used as reference points below are drawn from the range at https://calmcbdseeds.com, which goes 1:1, 2:1 and 20:1 and a top line at about 30 to one; the genetics holds the same whichever shop the packs came from.

Stage One: At the Breeder’s Bench

Cannabis settles whether it is going to make THC or CBD at one position on the genome. The gene there comes in two versions: one codes the enzyme that turns the shared precursor into THCA, the other the enzyme that converts it into CBDA. Each plant holds two copies, one inherited from each parent, and the pair fixes the chemotype. Two THC copies make a THC-dominant plant. Two CBD copies give a CBD-dominant one. One of each gives a balanced plant, since the two forms are codominant and not one of them silences the other.

The balanced pack was made by pairing two balanced plants, both carrying one copy of each form. The 20:1 pack was made by crossing two plants which both hold two CBD copies and no THC copy in either of them. This one fact at the cross determines all that follows downstream, and the difference is already in the seed long before it is packed.

The Mendelian Split

Cross two balanced plants and the offspring sort out by the oldest arithmetic in genetics: a quarter get two THC copies, a quarter get two CBD copies, half get one of each. In a pack of 10 seeds that works out to, on average, around two THC-dominant seeds, two or three CBD-dominant seeds, and about five true balanced seeds. The pack is sold by its parents, and for half its seeds the label is accurate; in the case of the other half it does not. Calm CBD Seeds states the expected split on each balanced pack, which means the buyer sees before sowing that a portion of the plants are going to differ from the stated ratio.

The 20:1 pack has no such spread. Each seed got a CBD copy from each parents, every plant is going to be CBD-dominant, and the ratio on the foil applies to every one of them, give or take the ordinary variation in how total cannabinoid any given plant produces. The trade describe such lines “breed true” for chemotype; the term refers to precisely this absence of variation.

Where Nothing Shows

Here the two packs appear the same again, and the likeness holds longer than most growers assume. Chemotype leaves no trace on a seedling. Leaf shape, colour, internode spacing and growth rate are controlled by other genes altogether, and the different chemotypes of plant in the balanced pack come up indistinguishably from one another and from every plant in the 20:1 pack.

One real distinction during this stage comes from lineage not chemotype. Strains with strong hemp ancestry, and that covers some less developed CBD-dominant lines, are inclined to stretch rangier and branch more sparsely. A well-worked 20:1 line grows like any indoor hybrid; a early-generation one may still shows the hemp in its shape. Not one of these habit tells a thing about the ratio in the flower.

Stage Four: The Flowering Room

In flower the two packs start to give clues, and most of them mislead. Resin coverage is the first thing a grower judges, and it used to be a fair rule: early CBD-dominant strains showed visibly less resin than their THC cousins, a legacy from hemp. Modern lines have mostly closed that gap, and a less resinous plant from the 20:1 pack can perfectly well test precisely where the foil said. Trichome density and chemotype are inherited on separate genes.

Smell is worse. The terpene chemistry sits on still other genes, so the THC-dominant plant hiding in the balanced pack can be indistinguishable to the balanced one next to it, and either can be identical to a plant from the 20:1 pack. Growers who try to separate a balanced pack by nose at week eight are right about half the time, which is no better than leaving the plants unsorted at all.

How Late Is Too Late

Here the two packs diverge in a way that favours the grower of the 20:1 pack and the CBD-dominant plants sitting in the balanced pack. CBDA degrades rather slowly than THCA, so a CBD-dominant plant left a week past its peak retains the bulk of its cannabinoid content, where a THC-dominant one under the same conditions has by then started converting THC to CBN. The cloudy guidance still holds; it holds on account of the terpenes, which fade on any plant regardless the chemotype, and a late, rushed CBD flower tastes of little whatever the lab number is.

Why Each Plant Gets Its Own Label

The 20:1 pack can go into one jar. Each plant in it holds roughly the same ratio, and blending them alters nothing worth measuring. The balanced pack cannot be treated the same way. Blend its 10 plants in a single jar and the contents become a ratio that nobody’s foil could have promised, skewed by whichever plants grew most, and nothing on a subsequent test can pull apart the plants that went in.

The habit that saves the trouble is dull: cut the balanced pack plant by plant, dry each apart, number each, and try each one one at a time rather than after the crop is combined. This is the one stage in the entire process at which the different kinds of plant in the balanced pack can still be kept apart short of a laboratory, and then only for the reason that every one is at that moment in its own container.

Reading the Two Results

Send a few grams from each jar to a laboratory and the two packs at last become readable. For the 20:1 pack the reports arrive back clustered closely near the stated ratio, differing mainly in total cannabinoid content rather than in proportion. For the balanced pack they arrive back in three groups: some plants showing almost all THC, a few showing almost all CBD, and the majority sitting near one to one. Nothing of this result is a failure; it is the breeder’s cross written out as numbers.

Home test kits are sold for growers who cannot reach a lab, and most show whether THC is there but not how much. That is sufficient to separate the THC-dominant jars away from a balanced pack and insufficient enough to assign a ratio to the others, which suits the commonest use: knowing which of the 10 jars will surprise someone.

Hemp Threshold Versus Chemotype

The last stage where the two packs separate is legal, and it catches growers who assumed “CBD” was shorthand for “hemp”. The majority of jurisdictions define hemp by a THC limit, a fraction of a percent of dry weight, with the precise number varying by country and sometimes year to year. A plant from the 20:1 pack making twenty percent CBD at twenty to one also makes about one percent THC, which is many times above the majority of limits. Certified hemp lines are selected to keep total cannabinoid output low so the THC fraction remains under the line right up to harvest; CBD flower lines are bred for rich content and let the THC rise with it. A seller that gives only a ratio is describing a flower line; anyone who requires a compliant crop should ask for a tested THC figure at harvest and order nothing that cannot show one.

Beyond the threshold issue, the chemotype alters very little about the law on the seed as such. Where holding cannabis seeds is lawful and germinating them is not, the balanced pack and the 20:1 pack fall under the same rule as any other pack. Where the plant is permitted without restriction, the decision between them is the grower’s and nobody else’s. No part of this article is legal advice, and the rule which counts is the one in the place the seed will be grown, rather than the one in the place it was sold.