🇺🇸 Retired veteran, father, rock-climbing expert & rosin connoisseur
Welcome to the Ultimate Starter Guide to Pressing Flower Rosin!
Solventless cannabis concentrates like flower rosin are one of the most popular ways to enjoy cannabis and its therapeutic effects. Not only is rosin incredibly pure and potent, lacking any chemical additives or solvents used for processing, but it’s easy to make at home. With a few grams of quality cannabis flowers, a press, some basic gear, and knowledge of the process, you can get started pressing exceptional flower rosin today!
The following guide was designed to help you navigate your initial setup, purchase the basic equipment needed, understand the variables of time, temperature, and pressure during extraction, cover common mistakes to avoid, and provide simple tips to keep in mind when pressing flower rosin.
Unlike other extraction techniques that utilize chemical solvents and closed-loop systems, the process of pressing flower rosin is straightforward, simple, and easy to accommodate in a small space with a limited budget. Apply heat and pressure to cannabis flowers and you get flower rosin!
Using a press and temperatures-controlled plates (even a hair straightener will work), heat and pressure are applied to cannabis flowers loaded in filter screen bags, known as rosin bags. This heat and pressure causes the trichome heads on the cannabis flowers to burst, and the resulting oils to liquefy and run through the filter bag. The outflowing cannabis concentrate, which runs from the bag and onto parchment paper for collection, is the flower rosin we’re after.Rosin captures the essence of the cannabis plant, but it won’t transform mediocre flowers into fire rosin. Quality rosin all begins with quality starting material. So let’s start by talking about quality genetics.
Which Strains Am I Working With?
Quality should be the ultimate goal when pressing flower rosin. Without quality cannabis flower, quality rosin isn’t possible. Seeking the most worthy cultivars for the job is a great first step to getting started. See the list of best strains for pressing rosin here.
Regardless of which cultivar, or strain, you’re using, the flower should be dried and only very lightly cured for extraction. The fresher the better, but the bud won’t yield quality rosin if it’s pressed while still too wet. Flowers should hover closer to 60-65% humidity before pressing, which can be tested with an inexpensive digital hygrometer (humidity gauge) and mason jars. Fill the jar with the flowers and the hygrometer and wait for the reading to stabilize.
Even with everything else dialed in, if you’re not working with great plant genetics, your rosin will be lacking. Don’t limit yourself to the list of best strains for rosin, but be open to experimentation and keep in mind the things to look for in a quality flower for pressing rosin: heavy trichome production and pronounced terpene profile. The buds should be loud!
Read more about how to find the best flowers for pressing rosin here.
Bear in mind that within the same cultivar, or cannabis strain, many phenotypes can exist, so experimentation with the strain is beneficial. To learn more about phenotypes and how to conduct a pheno-hunt to find the best genetics for rosin, check out this article.
How Much Source Material (Flower) Will I Have?
Knowing how much flower you plan to press will help you determine what type of press and what size of rosin plates you need to work with. If you’re only pressing a few grams of flower here and there, a hair straightener will be enough to get you started and familiar with the process. Learn more about pressing with a hair straightener here.
If you’re growing your own cannabis and have access to several ounces of flower at a time, building your own H-Frame press and purchasing quality rosin plates will probably be the most effective approach.
Do you need to grow your own cannabis to press rosin? Absolutely not! But it can be beneficial. Learn more here.
One of the first things to decide is which type of press you’ll use for rosin extraction. How much source material you plan to process will dictate what type of press you should use.
It’s not feasible to press pounds of flower with a hair straightener (but it has definitely been done!) and likewise you don’t need a 20-ton press if you’re just squishing a few grams here and there for personal use.
After you determine how much source material you’ll have and the amount of flowers you’ll be pressing on a regular basis, it’s time to come up with your rosin press set up.
What Kind of Rosin Press Should I Buy?
When you’re just getting started pressing flower rosin, a great option is to build your own press. You can use an H-frame hydraulic press in combination with a set of rosin plates and be good to go. This homemade approach is not only cost-effective, but it gives you the chance to customize your setup to best fit your situation. Learn how to build your own rosin press here.
Also, check out this article for a good review of the best types of presses for rosin.
In addition to the press itself, the rosin plates you choose will be a key component of the process. Quality aluminum rosin plates ensure accurate and consistent heat delivery, a critical variable to control. Find premium rosin plates from The Press Club here.
What Other Equipment Do I Need?
So far we’ve reviewed plant genetics, considered the amount of cannabis flower you’ll be pressing, and which type of rosin press best matches your expected rosin production volume. Let’s look at the list of additional equipment you’ll need.
Rosin Bags - filter bags that hold the cannabis flower and keep unwanted plant material, lipids, and other contaminants from mixing with the final product. Filter bags also help maintain consistent pressure on the source material during extraction, thereby increasing rosin yields. 90, 120, and even 160 micron bags are good for pressing flower rosin.
Parchment Paper - parchment paper is used to catch the fresh rosin immediately after it’s extracted through the filter bag. Use a sheet of parchment paper folded in half and place the rosin bag in between the layers (silicone-coated side facing the rosin bag). Parchment paper allows for easy rosin collection after extraction and keeps rosin from staining your rosin plates. Find quality parchment paper here.
To see a more thorough list of equipment needed to press rosin, check out this article.
Flower Rosin Extraction Process Overview
- Choose correct micron rosin bag
- Load the rosin bag with flowers
- Pre-press the material
- Load the rosin bag into the press
- Preheat material
- Begin applying pressure and slowly increase pressure until max PSI
- Collect rosin from parchment paper
- Place in mason jar for curing
Selecting the Correct Size Micron Rosin Bag
Microns measure the fineness of the screen filters that comprise rosin bags. Higher microns (like 160) have larger gaps in the filter screen, while the lower microns (like 15) have very tiny holes. For flower rosin, we want to use rosin bags in the 90-160 micron range.
It’s a good idea to experiment with a few different micron sizes for each strain you’re pressing, as the optimal micron may be different for various strains. It’s also a matter of personal preference, so trying a few different micron sizes will help you find your ideal size.
Read more about microns and how to select the right micron here.
Packing The Rosin Bag
After you’ve chosen the size micron bag you’re using (and ensure the seams are on the inside of the bag), lightly break apart the cannabis flowers, removing the main stems. The buds should be handled carefully to keep trichomes from breaking off before they make it into the bag. No need to grind the flowers, just breaking apart into small chunks that you can pack into the bag is fine.
The most important thing to remember when packing the rosin bag with cannabis flowers is to eliminate any air gaps and empty spaces in between pieces of cannabis material. Ensure the bottom corners are filled in with cannabis and that cannabis is packed evenly along the sides and bottom of the bag.
Empty pockets within the flower will reabsorb rosin as it’s being extracted, thus decreasing total yield. Evenly and firmly packing the flowers within the rosin bag will prevent this.
Read more about how to pack rosin bags here.
After working the bag with your hands, use a pre-press mold to further compact the material and ensure that it’s spread evenly throughout the rosin bag. Pre-pressing the flowers locks the material together, further eliminating inconsistencies in the packing of the material.
Read more about why it's important to use a pre-press mold here.
Loading The Rosin Bag onto The Press
Now that the rosin bag is loaded with material and pre-pressed, it’s time to begin the extraction. Make sure your rosin plates are set to the correct temperature (more on temperature and pressure below). You can heat up the plates at the beginning of the process as you’re getting started with preparing the rosin bags, to give it a chance to reach the proper temperature.
Fold a piece of parchment paper in half and place the bag in the middle, between the two sides. Slip the folded parchment and rosin bag horizontally in between the plates and lower the plates so they’re just touching the top and bottom of the rosin bag.
You can also use the Bottle Tech Method and load the rosin bag vertically, which helps control pressure during extraction. Read more about Bottle Tech here.
With the heated plates barely touching the bag, let the material preheat for 30 seconds. The idea is to let the plant resins begin to melt and prime the oils for their flow away from the material once full pressure is applied.
Now it’s time to apply the full pressure. After preheating for 30 seconds, gradually increase pressure, reaching a maximum PSI toward the end of the press. It’s very important to gradually ramp up to full pressure, which helps maintain a steady flow of rosin throughout the press. If full pressure is applied all at once, there’s a higher risk of rosin bag blowouts and a reduction in the even flow of rosin.
The total duration of the press should be in the 90-120 second range, but you can continue to press as long as you notice rosin still flowing from the filter bag and onto the parchment.
The optimal temperature range for pressing flower rosin is around 180-220 degrees Fahrenheit. Lower temperatures have a tendency to yield rosin with a more batter-like consistency, while higher temps can produce rosin with a shattery consistency.
When pressing flower rosin, it’s important not to measure pressure by the gauge on your hydraulic rosin press, which is just the reading of the internal pressure created within the hydraulic system. The pressure we’re interested in is the Platen PSI, which is the amount of pressure being applied to the source material. You can learn how to calculate Platen PSI here.
Aim for Platen PSI in the range of 650-1000 PSI.
The right balance of heat and temperature is critical in achieving the highest quality rosin. As a rule of thumb, higher temps will facilitate higher yields, but at the expense of quality as additional terpenes are vaporized away which can negatively impact flavor.
Additionally, more pressure can produce heavier yields, but at the expense of quality in the form of extra plant material ending up in the rosin. As pressure increases, more of the fats, waxes, and lipids produced by the cannabis plant will be forced away from the source material and flow through your bag into the rosin.
At the end of the day, your rosin is your creation, and you have the freedom to experiment with all the variables discussed above to find the settings that work best for you and your favorite strains.
Curious about what to expect for yields? See this article which breaks down yields for different source material, including flower.
Collect the Rosin
One way to make collecting rosin easier is to use a cooling plate under the parchment paper. Keep a cold plate in the freezer, then immediately after extraction, take the plate out of the freezer and place the parchment with fresh rosin over the cooling plate. The cooler temperatures help to separate the rosin from the silicone-coated parchment paper.
Carefully peel the rosin bag away from the parchment paper (keep it aside, you can use it later), and use a rosin stamp to collect the rosin from the parchment paper. Then, place the fresh rosin in a sealed jar for storing and curing.
How To Cure Rosin
Best Ways To Use Rosin
Once the rosin is cured you can dab it, or find other ways to use your rosin. Here are some ideas about how you can use your rosin.
Want to reuse the pressed rosin bags, or rosin chips? Find out how to use the spent rosin bags and material in this article.
You’ve navigated the rosin extraction process and you’ve got some homemade flower rosin to enjoy. We hope this guide has been helpful in starting you off in the right direction. There’s so much more to learn and innovation with new ideas is one of the most exciting things about the solventless extraction space.
Remember to try to keep it simple. Complexity is the enemy of execution. Remain open-minded, experiment, and take notes as you progress and get more presses under your belt. By collecting data for each press, you can refer to previous results and accelerate your learnings as you adjust variables in the process. This article helps with taking notes and collecting data.
Need help getting started? Let us know in the comments.