People have heard the hype. Daylight neutral (autoflower) plants are the next big thing in cannabis. Their life cycle is short, allowing for several harvests a year, and they can grow and flower under as many or as few hours of light as they are offered. Plants remain small for easy harvest and biomass is mostly flower. And yes, it is a beautiful sight to see an entire field of finished flowers in July before others' male pollen flies.
But these plants are not for the inexperienced farmer. In fact, we tell most people they don't want to grow them. So before you jump on the bandwagon, here are some essential lessons in autoflower cultivation we’ve learned from thousands of acres of field trials over the last 4 years.
They are extremely sensitive
Autoflower plants just want to flower and the trickiest part is getting them to grow for as long possible before doing so. It is ingrained into their DNA to try to reproduce at the first signs of stress, after which they put all of their energy into flowering until they expire. Whether they are several days or weeks old – this holds true.
You need to grow a lot
With a shorter life cycle comes much smaller plants. They will need to be planted at a much higher density than full season - add in the guarantee of at least a portion of the crop that will grow only inches to a foot before flowering. This means if you want to fill your canopy you will have far less spacing between rows for weeding implements and overall just a lot more plants to look after. It also means you simply cannot expect the same yield off of a crop of autos as you would a well grown crop of full season plants. With our varieties we recommend a minimum of 4000 seeds per acre with 2' between plants and 4' between rows.
Timing is everything
When germinating auto seeds in a greenhouse prior to planting, be ready to get seedlings into the field within a week of them sprouting. They are extremely temperamental when it comes to getting rootbound, and when root tips hit the bottom of the container they are in, they must be transplanted. If you wait even a few extra days, you could be too late – plants may have already decided to start flowering and you won’t know until you see your field packed with 3” tall nugs. It’s cute, but extremely unproductive.
For germinating, we highly recommend using pre-made plugs with potting soil. These plugs allow for easy transplanting when it's time to move plants into the field. They make removing plants without damaging the roots a lot simpler. If roots are damaged, plants can once again decide to flower. OBC Northwest makes these Earth Pots that work great for us.
If you try a direct sow method, ensure that soil is kept borderline wet. For our direct sow trials we overhead watered multiple times a day. While we had decent germination rates in areas where it was wet, 60%, areas that did not receive enough showed about 20%.
Get to know your fields
Once in the field, environmental conditions play an even greater role with daylight neutral than with full season. If soil is too dense or roots are suffocated – flowering can commence. If there is an insect, rodent, or mammal that decides to chew on some leaves – same thing. It is extremely important to know your fields, and know your weaknesses.
Keep them out of the heat
From our trials we found that temperatures in the 100’s also cause autoflowers to do just that - so they are best started early and finished in June or July in climates with extreme heat. They can also be planted again in early fall for a quick late season crop.
Be on the lookout
One of the most difficult aspects of auto production is checking for male flowers. With fields packed full of small plants, you virtually have to crawl on the ground to look for pollen producing male sacs – even on a feminized plant. With greater numbers packed in, it’s a lot of work and poor management can result in a seeded crop with much lower cannabinoid yields.
A shorter life span
Our autos finish in 11-12 weeks (77-84 days) after emergence under ideal conditions. This means you can stick them in the field in early May and harvest in July. This is a huge positive for people in areas where pollination is an issue as male plants don't start releasing pollen until the fall. That said, be prepared to harvest in the mid-summer heat.
Field drying works
For us in Oregon, we found great success chopping spring planted autos in the middle of the summer and allowing them to dry right on the plastic. Temperatures are hot and dry, and plants dried quickly. While terpene levels are significantly lower, there was virtually no loss in cannabinoid content.
Be careful what you wish for
Above all, just be aware, autos aren’t easy. If you are growing a few plants in your front yard they can be absolutely ideal. For those looking to cover acres they are not so easy. Regardless, we are excited about their potential for farmers!