🇺🇸 Retired veteran, father, rock-climbing expert & rosin connoisseur
Hours of experimentation lead to lots of valuable insights when you’re pressing flower rosin. We’ve captured a few of our favorites to help you on your journey to ever-better pressing.
QUALITY IN, QUALITY OUT
The quality of rosin you collect is determined primarily by the quality of the flower you’re pressing. Given that your press is dialed-in, any shortcomings in your rosin can most likely be traced back to shortcomings in your flower. The importance of excellent material can’t be understated if your goal is truly connoisseur rosin. In essence, if you want to improve the quality of your rosin, look first to improve the quality of your material.
Also keep in mind that quality and freshness tend to be interconnected. Aim to press your material just after the flowers have been dried and cured properly. Longer cures and excessive dryness can lead to darker results at the press.
How well the plants were cared for during growth and flowering has more of an impact on your final product than the growing medium used. There doesn’t seem to be any difference in flower rosin from soil, hydro, or coco, however some strains tend to produce flowers more readily pressed into high-yield rosin than others.
Expect chunky indicas and robust hybrids to yield more than the airy sativas. The resin production on the flowers determines the yields at the press, and don’t forget that genetics play a critical role. Using strains that are known for their potency and production will ultimately lead to more sap on your parchment.
MASTER THE MICRONS
Using filter bags is standard practice for most seasoned extractors.While bags aren’t absolutely necessary to press flower rosin, they are the best way to prevent tiny pieces of plant material from getting mixed in with your final product. However it’s not enough to keep one micron screen size for all purposes. The goal is to maximize both quality and quality in parallel, and properly selecting the correct micron for the job is crucial.
90 micron is the lowest micron we recommend for pressing flower. Less than that and you start losing out on yields for only negligible increases in quality. For flower, 90 Micron is the best choice when optimizing for quality despite some loss to your yields.
160 micron is the highest micron for flower rosin, as above the 160 width you’re likely to sacrifice purity and overall quality of the final product as unwanted material is forced through the screen. 160 Micron gives you a good balance between yield and quality, for the times you want to optimize the total output from your material.
The material of your bags is a key consideration, as various materials perform differently with exposure to heat and pressure. Additionally, the way a specific micron performs in the press is dependent on material, since higher micron counts allow more material to pass through.
Stainless steel can hack into your yields and silk has too much stretch to be able to effectively track pressure. The ideal material is 100% food-grade nylon rosin bags, regardless of micron width.
MOISTURE IS KEY
Very dry flowers are like sponges. They’re thirsty for moisture and all-too-quick to soak up the quality rosin you’ve worked so hard to extract. With ultra dry flowers in the press, once the trichomes and oils begin to heat and separate from the plant matter, rather than flowing out of the flower and through your bag they’re reabsorbed into the super dry material and never make it out to your parchment. Needless to say, this has a significantly negative impact on your yield, as you don’t want your flower retaining the product.
So how do you know how dry is too dry? Before you start pressing the flowers, make sure that the relative humidity content of the buds is 55-62%. This is the range you should aim for to ensure the maximum amount of rosin will separate out of the flowers. You can use an analog hygrometer (found in cigar boxes) to read the relative humidity, or spend $25 on a digital Caliber IV hygrometer. This modest investment pays dividends and is the best way to go.
If your moisture levels are outside the ideal range, pick up some Boveda packs and mason jars which will quickly and easily adjust the moisture.
WATCH YOUR PRESSURE
Although flower rosin requires more pressure than kief or hash, assuming that more pressure continuously leads to better results is a mistake. The ideal pressure range for flower rosin is somewhere between 550 - 1,500 PSI at the plate. For us, maximum quality runs at the low end of that spectrum.
There are plenty of presses that easily generate more pressure, but the point of diminishing returns falls well below the max pressure that many presses on the market are generating. With too much pressure, your rosin will likely contain particulates and non-beneficial plant oils.
Here’s how to calculate your pressure: take the total force your press exerts and divide that number by the total square inch footprint of the bag (as opposed to the total square inch of the whole plate). The standard method of measuring pressure is actually another point of contention, which we won’t dive into here.
High quality flower with the proper moisture level pressed in 115 micron bags at 550 PSI can yield around 23-25% (or more). Have you reached yields like this? Let us know in the comments.
PLAY WITH YOUR TEMPERATURE
Discussions about temperature generally divide rosin enthusiasts into two camps: Cold Pressing and Hot Pressing. There are advantages to both approaches, and both sides offer compelling arguments for their preferred temperature.
The temperature of your press and the distribution of heat both dictate the speed and consistency with which your flower produce rosin. Whether you’re pressing flower, kief, or hash, there are two workable temperature ranges that you can experiment with:
Cold Pressing: 160°F - 190°F pressed between one to five minutes or longer. This setting often produces a budder or batter-like product. This temperature range optimizes terpene preservation sometimes at the expense of lesser yield.
Hot Pressing: 190°F - 220°F pressed between 45 seconds and three minutes. This setting frequently produces oily or shatter-like consistency. You can expect high terpene preservation if you don’t exceed 220°F and with the added benefit of increased in yields.
The sweet spot for us between overall quality and yield is between 210°F and 220°F. If terpene preservation and quality is your #1 goal, you should probably start colder and evaluate your results, however we have observed very little terpene loss in that range. Anything above 235°F can bolster yields, however you’ll likely notice reduction in flavor and terpenes.
Our advice: measure your methods and results, continue to experiment, and see what works best for you. Give us your insights in the comments section!
Working with high-quality flower is the most rewarding way to press and to dab from our humble perspective as rosin enthusiasts. We love the ability that flowers give us to preserve valuable terpenes while creating a truly unique expression of the cannabis plant.
As the knowledge that our community collectively holds continues to expand and accelerate, we’re excited by the constant experimentation and innovation that occurs. If something from your experience would lend itself to the tips and tricks above, we’d love to hear from you in the comments.