Harvesting cannabis in fall checklist & expert tips

Autumn/fall is the most exciting time of the year for the outdoor cannabis grower. Cannabis plants often display some autumnal hues in the buds and leaves as the nights become colder. All the hard work preparing grow locations and nurturing preferred outdoor cannabis seed varieties comes down to the last few weeks. Will the plants survive the damp nights and escape mold?

Dutch Passion have decades of expert outdoor advice and essential tips whether you are growing feminised seeds or autoflower seed varieties. This guide provides a comprehensive fall harvest checklist and expert tips to ensure your crop reaches its full potential, delivering top-shelf quality you’ll be proud of.

Basic tips for cannabis plants harvest in fall/autumn

Understanding your own climate is key. Many will harvest their feminised seed varieties around early October in the northern hemisphere (early April in southern hemisphere). But the precise harvest point will vary according to your latitude, altitude, local climate/microclimate, first autumn/fall frost date and a few other factors. 

Research well, understand when cannabis growers harvest in your region. Above all, choose and prepare your grow locations well. Buy the best outdoor cannabis seeds. If you grow at altitude that will mean selectively bred high altitude cannabis seeds like Snow Bud or Pamir Gold will give you a huge performance boost. You may have a long grow season and be able to grow all types of outdoor weed seed varieties, including the slower blooming ones. Or you may have a short grow season that forces you to lean more towards the use of autoflower seeds or fast feminised seeds. Here are some key considerations:

The role of shortening daylight hours to trigger flowering.

Most outdoor photoperiod feminised cannabis seed varieties start blooming when days shorten in summer to around 14 - 14.5* hours of daily light (or less). This is usually their trigger point to start flowering. They should be ready to harvest around 2 - 2.5 months later.

Fast feminised cannabis seed varieties (Think Fast is Dutch Passion’s best outdoor fast feminised strain) often start bloom around 4-5 weeks earlier than feminised strains - when daylight hours are approx 15 - 15.5 hours per day. This means they finish around a month earlier than traditional outdoor feminised strains. This early finish means that proven, fast-feminised seed varieties like Think Fast can be genuine game-changers for those with borderline climates at harvest time.

*Note. Outdoor strains generally start bloom when daylight lengths shorten to around 14-14.5 hours. But some specialist indoor cannabis seed varieties (not necessarily bred for outdoor cultivation) may only start to bloom once outdoor daylight hours reduced to nearer 12-12.5 hours. 

Temperature & humidity challenges in late bloom.

Cool overnight temperatures and morning dew on the buds will test the mould resistance of your selected outdoor genetics. Proven outdoor strains can be the difference between a harvest or none at all.

Protecting your plants from the worst of the fall/autumn weather.

Plants grown in containers can be moved under shelter (garage, greenhouse etc) in the event of wild/stormy weather. Plants rooted directly in the ground can’t be moved but you may be able to protect them with an overhead tarpaulin if windy/stormy weather is due around harvest time. 
If stormy/difficult weather is worryingly routine around the harvest time of photoperiod strains it could be wise to focus on faster blooming autoflower seed varieties.

Pre-harvest preparation checklist

Many outdoor growers tend to chop their plants down and bring them indoors for eventual trimming & drying. Guerrilla growers (in the forests, hills and mountains) often do a rough trim outdoors and take the semi-trimmed blooms back home for drying indoors. 

But in the days and weeks prior to harvest many growers will enjoy giving spending more time watching the blooms swell, develop and ripen. This is a good opportunity to monitor your plants and ensure conditions are as good as realistically possible. At the same time it’s worth thinking ahead to ensure the harvest process will go smoothly.

• Inspect plants daily (if possible) as harvest approaches. Check for mold and pests.
• Clean and prepare your harvest/drying space. This is often a well lit trimming room with a drying room nearby. Outdoor growers often have an indoor tent fitted with drying racks for the trimmed buds. A carbon filter, extraction fan and ducting will also be required.
• Check you have all the right tools: Trimming scissors, gloves, drying racks, hygrometers, jars, odour control measures. Maybe some alcohol to clean the trimming scissors.
• Plan your schedule: Many prefer to harvest in the early morning, before the sun gets out  for peak terpene preservation.
• Some outdoor growers feel that flushing their outdoor plants for the last 1-2 weeks with pure water (especially if grown outdoors in e.g. coco containers) gives the buds a cleaner final taste. However many disagree with the perceived ‘need’ to flush outdoor (and even indoor) grown cannabis.

Expert Tip: When drying indoors have a spare carbon filter ready just in case the existing filter starts to fail during the drying process.

How to know when cannabis is ready to harvest

Buy cannabis seeds from an experienced supplier and they should be able to estimate the approximate finishing date for a given strain in your country/latitude. The experienced cannabis grower can augment this approximate harvest date with visual clues to know when the plant is nearing harvest.

• Trichome method: Many growers monitor trichome appearance and harvest when the trichomes are mostly cloudy and starting to turn amber.
• Pistil color method: Pistils are the ‘hairs’ that grow from the buds. They start as white/creamy and often fade to orange/brown as harvest approaches.
• Leaf fade: (nitrogen depletion naturally yellows fan leaves). Often, but not always, cannabis leaves fade from a healthy green and display more autumn yellow colours as harvest approaches.

In general, indica strains tend to finish bloom slightly faster than sativa cannabis seed varieties. Feminised seed varieties often have a 5-6 month outdoor grow cycle. A ‘fast-feminised’ seed variety such as Think Fast might be ready in 4-5 months. An autoflower seed variety is often ready to harvest after around 3 months of outdoor cultivation. Some autoflower growers harvest 2 or even 3 successive outdoor crops each year.

Expert Tip: If your seedbank estimates a late-September finish for your preferred strain note that this is a rough approximation and not a precise guarantee. Phenotype variations can influence early/late harvest times. Difficult weather or poor grow conditions can also delay harvest a couple of weeks.  Don’t rely on calendar days alone—always check trichomes for accurate harvest readiness.

Step-by-Step cannabis harvest checklist

You bought the best outdoor seeds for your needs & location. You grew them well and monitored trichome appearance as harvest approached. The big day will soon arrive and your plants will be taken down. Here are a few useful tips:

• Choose a dry, cool day.  Avoid harvesting in wet/humid weather. This makes drying more difficult.
• Cut off individual branches (or the whole plant) carefully.
• Remove large fan leaves. Some will fully trim the buds.
• Hang-dry whole/part branches OR use drying racks for smaller buds.
• Maintain an ideal drying environment: 60–70°F (15–21°C), 50–60% RH, in the dark, with gentle airflow.
• Once the branches ‘snap’ (rather than bend) it is an indication that the plant is near the correct dryness level for curing jars to be used.

Expert Tip: Slow drying (10–14 days) preserves terpenes and smoothness. Those growing on their own property will enjoy a leisurely harvest. Those growing in the countryside may face a nervy drive back home with their freshly harvested blooms. Stacked air-tight containers are strongly recommended along with an adherence to traffic speed limits.

Trimming: Wet vs. Dry

Is it best to trim your cannabis plants while they are wet or dry?  There are pros and cons each way…

Wet Trimming

Pros:  

• Easier to trim: Leaves are turgid, making them easy to cut. 
• Faster drying: Smaller buds dry more quickly, reducing mould risk. 
• Better in humid climates: Less plant material lowers humidity during drying. 
• Cleaner cuts: Fresh leaves make precise trimming easier.

Cons:  

• Sticky and messy: Resin will make tools and hands/gloves sticky & oily. 
• Time-sensitive: Must be done immediately at harvest, no excuses!

Dry Trimming

Pros:   

• Less sticky & messy: Some feel that dry leaves are easier to handle and clean up. 
• Flexible timing: Can be done days after harvest. No need to stress about an intensive full trim on harvest day. Instead chop and hang the plants/branches… and relax.

Cons:  

• It can be harder to trim: Dry leaves are brittle and curl. 
• Trichome loss. Many growers dislike seeing so many trichomes fall off their buds during dry trimming - one of the reasons many prefer wet-trimming.
• Longer drying time: More plant material also increases mould risk. 
• Space-intensive: More room required for drying/hanging whole plants compared to wet-trimmed buds which can be dried in compact racks/net-shelving.

Expert Tip: Save trimmed foliage and sugar leaves for hash, edibles, or concentrates. If you can’t be bothered making cannabis concentrates immediately you can always freeze the trim for later.

Curing for maximum flavour & potency

Once the buds have been dried (usually for around 1-2 weeks) they will still have a ‘fresh grass’ chlorophyll smell if smoked/vaped. But allow your buds to cure over a month or two and you will really see the flavours of the cannabis terpenes mature and improve.

• Step 1: Transfer the dried buds into airtight glass jars. Keep these in the dark - UV light degrades the cannabinoids and terpenes in your buds.
• Step 2: Open (or ‘burp’) jars daily for the first 1–2 weeks. This releases moisture.
• Step 3: Store at 60–65% RH, with humidity packs if preferred. Silica gel humidity control packs are useful for precision humidity control.
• Step 4: Cure for at least 3–4 weeks (longer cure gives a smoother smoke, with less of a fresh chlorophyll scent).

Expert Tip: A properly cured bud can last a year or two if stored in an airtight container in a refrigerator without losing significant potency or aroma. 

Common harvest mistakes to avoid

Many outdoor crops have been ruined by a badly planned harvest. A little extra thought given before harvest can go a long way towards a final successfully cured harvest.

• Harvesting too early or too late. Sometimes you have no choice. If bad weather is forecast many growers will harvest early than risk a serious beating from a 1-2 day storm. But if the weather is kind you can monitor trichome appearance and pick the perfect harvest point for your personal taste.
• Over-drying (crispy buds, terpene loss). Monitor your buds every day during drying and make sure you don’t over-dry them and lose all the terpenes. Many find around 10 days of drying to be a sweet spot, but that will depend on drying conditions etc. Drying your buds inside paper bags is one way to slow the drying process, allowing you more control.
• Skipping the curing stage. Yes, you could save yourself a few weeks by skipping the curing stage. But no serious grower would consider it. To get the best from the buds, spend a few weeks curing them and watch the flavours amplify!
• Poor airflow can increase mould risk. Avoid stale air spots in your drying room. These are areas where mould can thrive. Use a fan to mix the air and an exhaust fan to remove stale air and introduce fresh air.
• Using plastic bags instead of glass jars for storage. Yes, a few zipper-lock badges from the supermarket are cheap. But they allow the flavour and terpenes to constantly leak out. Glass mason jars will last years - get some in time for your harvest.

Bonus tips for a successful fall harvest

The key to a successful harvest is to be able to match your specific climate to the most appropriate outdoor marijuana seed varieties:

• Know your grow season well and understand, realistically, the length of the outdoor grow window at your location.
• Get the best outdoor strains that will finish in time at your location. Select indica, sativa or hybrid genetics. Many will be able to grow traditional outdoor feminised seed varieties. But some growers will be better served by fast feminised strains, high-altitude strains or autoflower seed varieties

In addition be sure to monitor your local weather closely. If growing multiple strains, label branches or jars to avoid mixing them up during trimming and curing. A dehumidifier can be useful to keep your drying room in the 50–60% RH sweet spot.

Once you get accustomed to routine top-drawer harvests you may want to experiment with longer curing: For premium buds, try curing for 6–8 weeks. The difference in smoothness and aroma is worth the wait and offers you something you won’t find in many dispensaries/coffeeshops.

Protect Your Harvest: Store your cured buds in a cool (below 20ºC/70F), dark place to prevent degradation. Vacuum-sealed jars are sometimes used to extend shelf life. Some growers put their buds in the freezer if they don’t intend to use them for a few months, this offers great preservation.

Conclusion

Harvesting cannabis in autumn/fall is a rewarding process, but one that does demand a certain attention to detail. Get it wrong and you risk losing month’s worth of effort. By following this checklist:

• Preparing thoroughly
• Timing your harvest with trichome monitoring
• Drying and curing with care
• And avoiding common mistakes

….you’ll maximise your crop’s potency and flavour. 

The cooler days and vibrant colours in autumn/fall set the stage for the harvest, but it’s your precision and patience that transform good buds into great ones. Use these tips, and you’ll be enjoying smooth, aromatic, and potent cannabis for months to come. 

If your next outdoor grow is on a strict budget then check out the ongoing Dutch Passion seed sale with some strains on offer at half price. 

Happy harvesting!