Can I start seeds in July and harvest in October?
Yes you can! Although most growers would, perhaps correctly, point out that a July start is a little late if you are aiming for maximum yield. Many outdoor growers would hope to germinate their cannabis seeds a couple of months earlier than July in order to give their plants the best chance of reaching their true genetic potential.
That said, you can germinate your seeds in July and still get a good quality harvest. If you are interested in knowing more about how to grow cannabis in summer, even after a late start, we have some great tips and info.
“When is it too late to plant cannabis for summer?” is a common question from outdoor growers. The answer depends partly on your local climate and the type of cannabis seeds you are hoping to grow.
With some expert advice on the best type of seeds for your situation (autoflower seeds vs feminised seeds), growing cannabis in summer is very straightforward. Lots of people get great results and so can you!
Pros and cons of starting cannabis seeds in summer
The summer solstice (longest day) is June 21st (Northern Hemisphere) and December 21st (Southern Hemisphere). Regarding the summer solstice, cannabis is generally recommended to be planted outdoors before the solstice. This remains good advice, but for many growers it is also possible to plant your cannabis seeds after the summer solstice and still get a harvest in the autumn/fall.
Advantages of seeding cannabis in July for northern Hemisphere growers (or January for Southern Hemisphere growers):
- The warm summer weather has already arrived, your growing season is already here!
- No risk of losing your seedlings due to an unexpected late frost.
- Guerrilla growers will already have lots of wild plants growing rapidly, perfect to hide your cannabis plants behind!
- There is still time left for a harvest, even if it’s a slightly shorter remaining grow season.
- You can look forward to seeing your plants thrive outdoors immediately in the mid summer conditions.
The disadvantages of starting cannabis seeds in July also need consideration:
- In general, your soil will be drier for your seedlings. Root growth is more difficult in dry soil so watering needs to be more frequent while the plants are young and more vulnerable to the heat.
- Black plant containers can become extremely hot in direct sunlight. In the worst cases this will bake the root ball, dehydrating the soil and the plant. This can kill the plant within a day or two. Keep plant containers in the shade, perhaps wrapped in a reflective white cover. Avoid putting plant containers on hot tiled surfaces.
- Plants germinated late in the season will likely be smaller than they would have been with an earlier start. This will mean smaller yields.
- Young plants may not cope well with direct midday sun in the hottest part of summer. Consider living them some shelter/shade from the sun between midday until around 4-5pm in extreme conditions. Perhaps under a tarpaulin or similar.
- With a short vegetative period the root network of your plants won’t be as deep or extensive as it would have been with a long vegetative period. This means you will need to give extra consideration to watering your plant more regularly.
How to grow cannabis outdoors in summer
Look for a private area where you can plant your cannabis seeds and allow them to develop without risk of discovery. Outdoor cannabis growers often have several guerrilla grow locations, just in case one of them is discovered. Unused field corners, waste urban land, river banks, hillsides etc all make great potential locations.
If local soil quality is poor you can supplement it with supermarket soil, well-rotted manure, general fertiliser etc. You can easily make a cannabis organic summer soil mix by blending some quality compost with some slow release organic nutrients such as those from BioTabs. Or you could add your own ingredients to enrich local soil e.g. bone/fish/blood meal, seaweed, worm castings, bat guano etc. If you can grow cannabis on your own land, balcony or patio that makes it easier to monitor plant development.
“How often should you water outdoor cannabis plants during summer” is another common question. In times of hot weather it is normal to water both at morning and night. If you use a larger plant container the roots have a larger available root space of moist grow medium which will allow your plant to manage for longer periods with watering.
If you root your plant directly into the moist earth (without a container) it allows you more latitude, you may need to water less frequently since the roots can source their own water unless in severe drought. When growing in containers you can assess the remaining moisture levels by lifting the container (if possible) to assess the weight. Or you may prefer to use a hygrometer in your plant container to measure moisture level in the root zone.
Growers in extremely hot regions often ask whether will cannabis grow outdoors in summer, in the south with hot temperatures. Unless temperatures are regularly hitting 35-40ºC for prolonged periods then you should be able to get the plants through to harvest.
Planning your grow after a late outdoor season start
If you are aiming to plant cannabis seeds in the summer, most growers aim to get their plants outdoors as soon as the weather is suitable. For growers in northern Europe that can mean waiting until the last frost has passed.
- At Dutch latitudes, or similar, growers often put their plants outdoors around late May.
- At southern Mediterranean latitudes you might place your seedlings outdoors in March.
Obviously, an earlier start allows your photoperiod feminised outdoor strains a longer period of vegetative growth and therefore a larger final result. But that doesn’t mean that you can’t start your feminised seeds in July, and accept a somewhat smaller final result.
Autoflowering cannabis seeds are generally recognised as being the fastest, simplest and easiest way to grow cannabis. They can grow from seed to harvest in around 3 months.
Having a spare pack of autoflower seeds in the fridge is always a good idea for outdoor growers contemplating a last-minute summer grow. Check out the Dutch Passion Seed Sale for the latest special offers.
Choosing the best suited seeds for a summer cannabis grow
If you’re planting your cannabis seeds in June or July you need fast growing outdoor strains. Autoflower seeds are particularly recommended for outdoor growers thinking of a late start.
If you plant your auto seeds in June (or early July) you should have a crop around late September or early October. If you can pre-grow your auto seeds indoors for a couple of weeks (under 24 hours of daily light) before planting them out that will speed up your plant development and final size even more.
Choose the faster autoflower strains if you are up against the clock with a late season grow. Some longer blooming autos (e.g. Auto Ultimate, Auto Glueberry) can take a few weeks longer than average, such autoflower strains are probably best avoided if you are on a tight schedule.
Recommended fast/tough auto strains include Auto Mazar, Auto Blueberry and Auto Blackberry Kush. All will do well outdoors and are fast enough to deliver a harvest even if planted outdoors late in the year.
Photoperiod feminised strains are also a good choice for a late season outdoor grow. Dependable strains such as Frisian Dew, Think Fast and Durban Poison are all recommended.
However, it should be noted that photoperiod feminised outdoor cannabis seeds germinated in July will only have around a month of vegetative growth before starting bloom. This will have inevitable consequences on size and yield. Expect a small/medium sized result rather than a monster outdoor plant.
Watering and feeding schedule for outdoor cannabis in summer
Watering requirements when growing in the middle of summer can be high. Growers in Southern Europe may see heatwave temperatures in excess of 30ºC for long stretches. This can mean watering your plant at morning and night. Some growers leave some water/nutrient solution in a tray underneath their plant container.
This can help the plant from completely drying out. Some growers remove their plant from direct sunlight in the middle of the day, or place the plant in shade to protect it from the worst of the midday heat.
Growers in cooler climates (e.g. Northern UK, Scandinavia) may still face hot temperatures though rarely as high and prolonged as those faced by growers with more Mediterranean climates. Watering and feeding schedules for growers in these regions will vary significantly.
Whether you are growing in a hot or a cool climate you will need to find the right watering schedule for your conditions. Even in the same grow location, outdoor conditions can vary significantly from one year to the next.
Flowering cannabis plants seeded in July
Autoflower seeds germinated in July (Northern Hemisphere) will probably start bloom during August and finish flowering in late September or early October. Many outdoor growers enjoy the often compact, squat and bushy nature of growing autoflowers outdoors. Autos can be easier to hide than 3-4 metre tall photoperiod monsters!
Autoflowering cannabis seeds also do very well in a greenhouse or polytunnel. As with feminised strains, a greenhouse helps protect your plants from the worst of the late-season weather. It’s something to consider if you have significant concerns about the October weather at your grow location/latitude.
Feminised strains planted in July will have a month (or less) before they show signs of bloom. That means it is more realistic to have modest expectations of the final plant size and yield. But even with a July start, you can still harvest some good quality buds in autumn/fall.
Cooling cannabis plants during summer
How to shade cannabis plants in summer? On the hottest days you may want to keep your plants out of the midday sun, if only for a few hours. Cooling cannabis plants during summer isn’t easy.
If grown in a container, move your plant to a shaded area. Some growers create shade for their plants with a tarpaulin, but this isn’t always easy when growing outdoors.
Avoid placing your plants on a hot tiled surface which can greatly increase temperatures in the root zone. Likewise, avoid black plant containers which will heat up in the sun and cook the root ball.
Even when a cannabis plant is badly dehydrated it can often recover after a few hours of cool conditions and plenty of water. After all, people have been growing cannabis in hot climates successfully for thousands of years.
The real issues happen if your plant is in mid bloom and hits a heatwave. Recovering from heat stress and dehydration is easier in vegetative growth then it is in bloom.
Professional growers do have a few options. Increasing CO2 content, for example in a greenhouse, allows plants to tolerate higher temperatures. Some greenhouse growers with blackout blinds equipped on their greenhouse have an easy way to shade their plants if temperatures reach dangerous levels.
Harvesting cannabis plants seeded in July
If all goes well, and it often does, your cannabis plants started in July will be ready to harvest around October. If the late season weather is poor, you may consider creating some kind of shelter/cover to keep torrential rain off your buds. With a little bit of luck you may see your plants grow steadily and supply you with some bonus winter buds.
For those growing in reasonable climates, it is also possible to get an early season auto harvest as well as a late season auto harvest. The following grow review from Denmark shows how even Scandinavian growers can get two successive autoflower harvests each year
Grow cannabis from seed to harvest in 3 months!
Even if you have left it late to plant your cannabis seeds this year you can still get a decent harvest with a short 3-4 month summer grow. Feminised seeds, and perhaps especially autoflower seeds, are great options for growing cannabis in summer even with a late start. If you are thinking about a late season outdoor grow remember it’s easy, secured and fast to buy cannabis seeds online!
What’s the Best Time to Start an Outdoor Cannabis Grow?
I t’s amazing how quickly the world can change, isn’t it? In the past 25 years, cannabis has moved from an illicit substance relegated to the shadowy corners of the illicit market to an “essential” industry amid COVID-19. In many states, local cannabis laws allow you to grow your own, and why not? When you grow your own, you can do your own quality control, know the purity of your product, and manage your own supply.
Luckily, you can start your own grow in a container as small as a flower pot. If you’ve got some space in your yard to grow weed outdoors, even better. So this may leave you wondering, when should I plant my cannabis outdoors? Luckily, there are some general date ranges to help guide your growing plans.
Regardless of which climate you’re starting in, when Spring Equinox comes around, start germinating your seeds. Make sure those plants get outside by Summer Solstice in June, then harvested around Fall Equinox.
For more specifics about how to protect your outdoor cannabis grows from the elements or whether you should grow indoors, outdoors, or in a greenhouse, check out the linked articles. Better yet, look into a book by celebrated cannabis growers like Ed Rosenthal’s Marijuana Grower’s Handbook, and of course, every green thumb’s favorite, The Farmer’s Almanac.
For a (shallow-ish) deeper dive into what to expect when growing cannabis outside, here’s a look at optimal grow times for regions across the U.S.
When to Grow Weed Outdoors by Region
Northwest (Northern CA, OR, WA)
When you grow outdoors in this loamy region you’ll never have to worry about getting enough rain. However, mold development and lack of sunshine can make growing outside a more difficult proposition.
Hybrids that flower earlier are suggested as the most successful grows, especially in Washington and Oregon. California plants can be put in the ground earlier due to the region’s warmer weather. Your best clue indicating that it’s time to start your outside grow is when daylight hours increase and the temperature starts to warm.
- Preparing Your Colorado Soil for an Outdoor Marijuana Grow
- How Long Does it Take to Grow Cannabis Plants?
- The Best Strains to Grow Outdoors
- The Flowering Stage Of Cannabis Week By Week
Midwest (IL, MI, Eastern CO)
This region is tricky because the weather is highly variable; rainy and muggy, and/or hot and dry. Winter may come early to this region, so choosing an indica-dominant hybrid strain might be your best bet, since their flowering times are shorter. Try to shoot for germination after the final frost of spring has passed in these regions.
Northeast (NY, MA, ME, VT)
With its rich soils and abundance of water, the northeast region can be a great place to grow cannabis outdoors, especially if you choose an early harvest strain that can finish up before fall kicks in. The best time to move your plants outside in this region is the middle of April, when days are longer.
Southwest (Southern CA, NV, AZ, NM, CO)
If you choose to grow outdoors in this scorching climate, be prepared to pay attention to the temperature, where highs that regularly exceed 100 degrees Fahrenheit will slow your plant’s growth. Sativas and sativa-dominant hybrids do well in this environment because of their lineage tracing back to the equator, where the weather is uniformly hot.
However, the dryness of the region means you’ll also have to carefully monitor your watering routines. Before moving your plants outside, make sure the last frost has passed. This last note is especially important in this region, as sudden, sporadic snowfall is common, so keep an eye on the weather.
Though home cultivation is not yet allowed in the Sunshine State, many new medical producers getting into the industry are starting to grow outdoors, and there are a few things to be aware of if you’re licensed in the industry. The temperatures in Florida might be good for cannabis growing, but the humidity definitely is not.
In fact, because of all that moisture in the air, it’s best to avoid indica strains and grow sativas instead to avoid the mold that inevitably comes along with humidity. In this region, you could start the germination process as early as February. Just make sure that the last frost has passed before moving plants outside.
Of course, there are many different factors that go into the timing of an outdoor grow, and the weather will shift year-to-year. Use these estimates as rough guidelines and adjust as needed. Happy growing!
What’s the best time to plant outside in your area? Share in the comments!
Erin Hiatt is a New York City-based writer who has been covering the cannabis industry for more than six years. Her work – which has appeared in Hemp Connoisseur Magazine, PotGuide, Civilized, Vice, Freedom Leaf, MERRY JANE, Alternet, and CannaInvestor – covers a broad range of topics, including cannabis policy and law, CBD, hemp law and applications, science and technology, beauty, and psychedelics.
Erin’s work and industry insights have been featured on the podcasts The Let’s Go Eat Show, In the Know 420, and she has appeared as a featured panelist on the topic of hemp media. Erin has interviewed top industry experts such as Dr. Carl Hart, Ethan Nadelmann, Amanda Feilding, Mark A.R. Kleiman, Dr. James Fadiman, and culture icons Governor Jesse Ventura, and author Tom Robbins. You can follow her work on LinkedIn, WordPress, @erinhiatt on Twitter, and @erinisred on Instagram.