So we know that pressure and heat are the two biggest elements to get the oil off of the flowers, but what else is essential?
The humidity levels of your buds play the next biggest role in regard to yields when pressing rosin. Buds that have been left out in the air to dry oftentimes will be well below the optimal levels for squishing rosin. This is dependent on the relative humidity of the environment. This is why we like to take our buds and store them in an airtight container with a two-way humidity pack to maintain a humidity level that is proper for squishing rosin. What we are finding is buds that are stored with relative humidity (RH) of at least 55% but up to 65% produce the best yields, with better yields at 62 or 65% RH. Buds stored with an RH above 68% are at high risk of growing mold. Once your buds have mold, they are unusable. Please be sure to always store your buds under the proper humidity levels (55-65%) for the safest consumption. If you need to dry your buds out a bit to vaporize, simply take them from the jar for 15 minutes and let them air dry then it is dry enough for fast vaporization.
Trichomes are the other element. It is a simple fact the more trichomes that are present on your buds, the more rosin will be generated. The best way to identify the trichome density of your material is to use a jeweler’s loupe at least 30-60x, a digital microscope can also be used for even higher magnification. If you do not have a way to see the trichome coverage, the other test is to squish a nug in-between your fingers and release it, now if your fingers stick well when you press them back together, there is likely good trichome density and expect at least average to high yields.
The age of your buds also matters. Freshly harvested and dried buds will likely have a good mixture of clear, cloudy, and amber trichomes, so the end result can vary from pale cream to yellow depending on the strain. Older buds that have been curing for a while will have undergone some form of decarboxylation. Decarboxylation is a natural process that occurs with cannabis as it is exposed to oxygen in the environment, and the trichomes continue to mature and darken. The rosin harvested off of older buds will generally be darker in color. It should be stated that darker rosin is still wondering if the starting material is good and the technique is correct!
What about live plant material? Well, live plant material has a lot more moisture content in the buds than we want when squishing rosin, so the most effective method for making live rosin would be to first harvest the trichomes from a live plant in the form of the hash.