Marijuana Grow Calendar: Southern Parts of the United States

Marijuana Grow Calendar Southern States USA
September 09, 2020

One of the challenges for beginners is not knowing what to expect when growing marijuana for the first time. In the outdoors, the plants are reliant on the climate. Being aware of when you should germinate, when the flowering period starts, and when to harvest helps eliminate heartache. More importantly, you can plan ahead and ensure that all the necessary things are prepared, ready to use when needed. In this article, you will see the recommended growing schedule for the Southern parts of the USA, including Hawaii.

Marijuana Outdoor Grow Calendar for Southern USA

The outdoor growing season begins in May, but you can get ahead by starting preparations in February. An early start gives you plenty of time to obtain everything you are going to need instead of cramming at a time when you need the most.

Before proceeding, there are a few things you need to know to better understand this sample growing schedule covering the southern half of the United States and Hawaii.


  • The day length and temperatures are averages based on the states of California, Texas, and Florida.
  • Growers in the Southern West Coast have the most sunshine while also having cooler average temperatures.
  • It will be hottest during summers in the Central USA; spring and fall in the Southeast.
  • Hawaii has the shortest summer days.


Southern USA Hawaii
Average Day Length (hours) 10.5 to 11.5 11.5
Average Temperature (°F) 49 to 80 67 to 81

This time of the year, frost should no longer be a concern for most Southern states. It is also the best time to choose the strain and buy the seeds. Considering that the growing season is long, you can pick any Sativa cultivar if euphoric cerebral high is your preference. For full-body relaxation, then choose an Indica strain.

Note: Most Indica strains trace their roots to the harsh, cold region of the Hindu Kush mountain range. Modern hybrids, however, are better able to tolerate hot temperatures. So, they should grow nicely in warm climates.

If you have not done so, think through the cultivation steps from start to finish. List everything that you need to prepare. These would include pots, mediums, nutrients, testers, and others. Of course, do not forget to order the seeds from Homegrown Cannabis Co., too.


Southern USA Hawaii
Average Day Length (hours) 11.5 to 12.5 11.5 to 12.5
Average Temperature (°F) 50 to 81 68 to 82

Summer is around the corner. In central states, frost is definitely no longer a concern. On average, you would have around 12 hours of daylight. It would be an excellent idea to start germinating seeds by the windowsill. If need be, you can augment or extend the “light on” cycle using CFLs.


Southern USA Hawaii
Average Day Length (hours) 12.5 to 13.5 12.5 to 13
Average Temperature (°F) 55 to 84 70 to 83

Except for Hawaii, most of the Southern USA will see a slight rise in temperature. The days are also getting longer, with most places averaging 13 hours of daytime. You could stop using CFLs by mid-April as long as the weather is good, and the seeds could receive at least 13 hours of light exposure.

The Southeast usually would have the hottest spring temperature in the Southern half of the USA. Hence, if you live in this area, it is possible to take the young plants outdoors. You can do so as long as the outdoor temperature is at least 70°F. In the evenings, you would still have to bring them inside the house to protect them from the elements and pests.

If you are planning to grow one of our autoflowering strains, you still have time to obtain the seeds, but you have to do it quickly.


Southern USA Hawaii
Average Day Length (hours) 13 to 14.5 13 to 13.5
Average Temperature (°F) 60 to 87 71 to 85

While some places may have felt like summer a month ago, it is now officially the spring season in the Southern USA. Your plants no longer have to be confined inside the house. Take them outside and let them bask under the glorious sun.

For autos, start planting by mid-May. They will have plenty of sunshine to harness and should be ready for harvest by August. One thing to note, if you live in Hawaii, is to make sure to pick strains that do not require as much light. Summer days in this state are the shortest in the whole United States.


Southern USA Hawaii
Average Day Length (hours) 14.5 13.5
Average Temperature (°F) 60 to 91 74 to 87

In June, especially between the 18th and 24th, your plants grow at their most vigorous rate. Be sure to provide adequate nutrients to maintain explosive growth. Around this time, too, autos would transition to the flowering stage.

On the other hand, Hawaii starts to have shorter days – much more so than the rest of the United States. Compared to California, for example, they would have 90 minutes less daylight.


Southern USA Hawaii
Average Day Length (hours) 13.5 to 14.5 hours 13 to 13.5
Average Temperature (°F) 65 to 93 75 to 88

The hottest time of the year is upon you and the plants. They should, by now, start to produce pistils. Regardless if you are growing regular or feminized seeds, now is an excellent time to start being vigilant when identifying the gender of your plant to ensure that you remove male plants as soon as you identify them to ensure that your female plants flower and produce buds.

As for auto-flowering plants, you would now see large clusters of flowers. Also noticeable are the trichomes that they are producing.


Northern USA Alaska
Average Day Length (hours) 13 to 14 hours 12.5 to 13
Average Temperature (°F) 65 to 95 75 to 89

If you grow auto-flowering plants back in May, you will harvest those buds this month. Make sure that it is the right time by observing the colors of the pistils and the trichomes. Before you can consume the buds, you will still need to dry and cure them.

For photoperiod plants, you might be able to harvest the buds, but that depends on the strain as much as it does on the daylight hours. By this time, the average would be between 13 to 14 hours. Ideally, it should be before daylight hours dip down to 13.


  • In the Southeast and Hawaii, the growing season is shorter than in other parts of the country. That is why it is preferable to grow auto-flowering strains.
  • At less than 14 hours of daylight, photoperiod plants will be on the last leg of the flowering phase. If they still need more time to develop buds and trichomes, you may have to bring them indoors and provide powerful HPS/LED lighting.


Southern USA Hawaii
Average Day Length (hours) 12 to 13 hours 12 to 12.5
Average Temperature (°F) 64 to 89 75 to 89

Fall comes at the end of September. Although that may not be evident in some parts of the Southern USA with regards to temperature. The shorter days towards the end of the month, though, is noticeable. It tells you and especially the plants that the growing season will soon be coming to an end. Most strains today will be ready for harvest, except some that need a little bit more time – usually Sativa strains.


Northern USA Alaska
Average Day Length (hours) 11 to 12 hours 11.5 to 12
Average Temperature (°F) 60 to 86 74 to 87

Autumn has arrived, and that signifies the end of the growing season. For plants that need more time, this is when you will harvest them for their precious buds. Because of the lower temperature, be mindful of excessive moisture and bud rot. If some pathogen would thrive can bring about this disease, act quickly and you can remedy it, thus saving the plants.

Recommended Strains

Considering the colder climate in the northern region, it makes sense that most people prefer Indica strains. For one, they have a quicker life cycle. More importantly, most of these strains have their origins in the harsh, cold climate of the Hindu Kush region and are therefore accustomed to colder temperatures.

Jack Herer Feminized

  • Genotype: Sativa hybrid
  • THC: 24%
  • Flowering Time: 8-9 weeks; Late September to early October
  • Yields: Heavy
  • Recreational: Expansive and creative
  • Medical: Depression and stress

Blue Dream Feminized

  • Genotype: Sativa hybrid
  • THC: 17-24%
  • Flowering Time: 7-9 weeks; October
  • Yields: Heavy
  • Recreational: Happy and relaxing
  • Medical: Stress and depression

White Widow Feminized

  • Genotype: Indica hybrid
  • THC: 18-25%
  • Flowering Time: 7-9 weeks; Late October
  • Yields: Medium
  • Recreational: Creative and euphoric
  • Medical: Anxiety and depression

White Widow Autoflower

  • Genotype: Indica hybrid
  • THC: 19%
  • Flowering Time: 8 weeks from seed to harvest
  • Yields: Low
  • Recreational: Happy and relaxing
  • Medical: Anxiety and ADHD

Lots of Sun

The United States is a diverse country, with the climate in the northern and southern parts varying greatly from one another. As you can see in this growing schedule for Hawaii and the Southern USA, marijuana plants need sun – plenty of it, too. Hence, in planning your schedule, take this into consideration.