The Best Medical Strains to Grow in Illinois

Illinois’ climate ranges from moderately to severely challenging for growing cannabis. On the one hand, the state has hot and humid summers that many cannabis varieties love. And while Illinois’ climate is split between its northern region with its humid continental climate and its southern region with its subtropical climate, they at least share the same type of summers. The only difference between the two regions is South Illinois’ milder winters.

But on the other hand, Illinois is also known for its fickle weather. It gets at least 50 days of thunderstorms each year during its spring and summer seasons, and it’s difficult to tell when the weather’s going to turn since the storms develop quickly and can occur with little to no warning. Additionally, Illinois often has tornadoes, typically around spring, but they can appear later or earlier in the year.

The best way to grow cannabis in Illinois is with autoflowers. Their short growing cycle lets you get ahead of the state’s fickle weather while taking full advantage of its hot and humid growing seasons. Another way to keep it outdoors is growing marijuana in a greenhouse, where you can grow photoperiod plants. Now that you know the growing challenges of the state, all that’s left is to choose what strain you want to cultivate. This list provides 10 of the best medical strains to grow in Illinois.

Grape Octane

When growing cannabis strains in an area where the weather’s fickle and can easily become unfavorable for marijuana plants, you’d want a strain that’s at least easy to grow. And Grape Octane is just that and more. It’s a 50% sativa and 50% indica hybrid that grows in various climates, including temperate and continental climates, where temperature drops often occur.

Grape Octane Feminized Seeds

Most Cannabis growers want three things: great yields, potent strains, and a great taste. Our Grape Octane feminized seeds deliver all these things and more in a straightforward grow.

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That means that this hybrid’s growth won’t be affected by Illinois’ sudden changes in weather that cause temperature fluctuations. And, what’s more, is that Grape Octane comes with an autoflower version that offers an even easier growing experience.

Grow this hybrid strain by buying Grape Octane feminized and autoflower seeds in our store. Download our Harvest Guide to pinpoint the best time to harvest your cannabis so you, too, can get 12 to 16 ounces per plant from this strain and 5 to 15 ounces from its autoflower.

Grape Octane cultivar profile

Harlequin

Are you looking for a high CBD strain? If so, then look no further than in Harlequin. This sativa-dominant strain is unique because it has a high CBD level of 10 to 15% and a low THC content of up to 7%. And while studies regarding CBD and its benefits are ongoing, a 2019 study claims that CBD helps decrease anxiety and improves sleep.

Harlequin Feminized Seeds

Harlequin is a sativa-dominant hybrid offering the best sativa and indica qualities. This strain delivers very effective medicinal uses with its reasonably high CBD levels.

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Regarding growing, Harlequin is a moderately challenging strain. The difficulty comes with the plants needing a nutrient-rich growing medium to flourish and a climate that doesn’t expose them to excessive heat that causes them to dry out. Illinois’ humid climate makes for a favorable environment, but it’s best to grow this strain in a greenhouse due to the state’s erratic weather conditions. Providing the ideal growing conditions for this sativa hybrid strain can yield up to 14 to 17 ounces per plant.

Read our full review of Harlequin, or buy Harlequin feminized seeds in our store, where you can also buy marijuana fertilizers to feed your weed plants and ensure their continued optimal growth.

Harlequin cultivar profile

Mimosa

Mimosa is a sativa-dominant strain that can thrive in temperate and continental climates with cooler temperatures of around 20-23°C (68-75°F). And with it having sativa genetics, it can handle more humid environments. This makes the humid continental climate of Illinois an area where cannabis plants can easily flourish.

Mimosa Feminized Seeds

Combining a citrus strain with the therapeutic Purple Punch, Mimosa delivers relaxing yet uplifting effects that any Cannabis consumer will love.

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Marijuana growers will find Mimosa cannabis relatively easy to cultivate. It doesn’t require extra effort but does benefit from being given the right amount of nutrients through fertilizers. For an even easier and more secure grow, try Mimosa Auto and harvest ahead of Illinois’ unpredictable and sudden thunderstorms.

Read our full review of Mimosa, or buy Mimosa feminized and autoflower seeds in our store.

Mimosa cultivar profile

Purple Punch

Purple Punch is an Indica-dominant strain that crosses two of the world’s most popular cultivars, Grandaddy Purple and Larry OG. The result indica hybrid was a potent strain with a THC content of up to 25%. And while research on the benefits of THC is still ongoing, a recent 2022 study suggests that it can help with chronic inflammation.

Purple Punch Feminized Seeds

The Purple Punch weed strain hails from the tropical island of Hawai'i. This hybrid is 80/20 indica dominant and first bred by Supernova Gardens in Kauai, Hawai'i.

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Under the ideal outdoor growing conditions, Purple Punch cannabis can yield around 23 ounces per plant. For Purple Punch to flourish, you must have a humid climate with plenty of warmth and sunshine. While Illinois’ climate does offer a hot and humid growing season, there is the matter of its erratic weather conditions with its sudden thunderstorms. Thankfully, Purple Punch has an autoflowering version with a shorter growing cycle to make sure you stay ahead of the state’s unpredictable weather.

Read our full review of Purple Punch, or by Purple Punch feminized and autoflower seeds in our store.

Purple Punch cultivar profile

Crystal

Created by crossing Northern Lights with White Widow, Crystal is an indica hybrid with qualities that surpasses its parents. This highly potent strain has a THC content of up to 25% and a considerable yield of 14 to 16 ounces per plant.

Crystal Feminized Seeds

Crystal seeds grow herb that delivers a well-balanced euphoria combining a cerebral high with a sedating body effect. This feminized Cannabis is 60% indica and 40% sativa.

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You need to provide the right climate to maximize Crystal’s yield. Like its parent, White Widow, this indica strain can thrive in hot, humid, and sunny climates with sudden temperature drops, making it one of the best marijuana strains to grow in Illinois. However, one thing about growing Crystal is that you must trim the plants when needed. Beyond that, Crystal is an easy strain to cultivate. Just be prepared for sticky, trichome-covered buds that look like crystals, hence the name.

Read our full review of Crystal, or buy Crystal feminized seeds in our store.

Crystal cultivar profile

White Widow

White Widow is the best cannabis strain to grow in Illinois. Its strong genetics produce resilient plants that can flourish even in climates with sudden temperature drops. And given that the state is known for its sudden thunderstorms, growing a strain that can resist temperature fluctuations is a must.

White Widow Feminized Seeds

Are you looking for a relaxing smoke to unlock your conversational and creative side? You are going to love our White Widow seeds!

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Regarding growing, White Widow is an easy strain to cultivate because of the hardy plants it produces. This Indica-dominant strain’s ease of growing is shown by the fact that it was a staple in Dutch coffee shops. It also helps that it’s a high-yielding cultivar that can produce 18 ounces per plant.

Grow White Widow by buying White Widow feminized and autoflower seeds in our store.

White Widow cultivar profile

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OG Kush CBD

OG Kush CBD is no different from its regular, high-THC counterpart. However, this version of OG Kush has a high CBD content of up to 15% and barely any THC (less than 1%). But when it comes to cultivating and tending to this strain, it is the same as you would when growing regular OG Kush.

OG Kush Feminized Seeds

OG Kush produces a mood-elevating, heavy euphoria making it great for people looking to wash away stress. Its blend of 75% indica and 25% sativa brings a balance between physical and mental experience.

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OG Kush CBD flourishes in climates that have sunny, tropical-like weather. However, OG Kush CBD cannabis can also grow in cooler climates thanks to its strong genetics and the hardiness of its plants. That said, growing this cultivar in an area with unfavorable conditions could lead to bug infestations, diseases, and mold. You can always grow OG Kush CBD in a greenhouse if your outdoor climate isn’t suited for this strain.

Grow OG Kush CBD by buying OG Kush CBD feminized seeds in our store, where you can also get plant protectors to ensure your plants are safe from diseases, mold, and other pests.

OG Kush cultivar profile

Gelato

Gelato is an excellent strain to grow in Illinois thanks to its fast-flowering trait. With a short flowering time of only 8 to 9 weeks, this indica hybrid allows you to harvest as early as October. If you’re looking for an even faster harvest, we highly recommend growing its autoflowering version, which has a much shorter growing cycle.

Gelato Feminized Seeds

Are you a marijuana veteran burdened by a high tolerance, looking for an easy smoke that hits hard every time? You are going to love Gelato!

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Regarding the climate Gelato cannabis flourishes in, this indica strain loves humid conditions that aren’t too hot or cold. This makes the humid climates of both north and south Illinois the perfect place to grow Gelato. Just remember the thunderstorms and tornadoes that occur in spring and summer.

Read our full review of Gelato, or buy Gelato feminized and autoflower seeds in our store.

Gelato cultivar profile

Zkittlez

Zkittlez is an Indica-dominant strain with strong genetics that lets it produce hardy plants. Zkittles is one of the easiest strains to grow and a great choice for any Illinois cannabis grower because the plant can thrive in the state’s humid continental climate thanks to high resistance to mold and mildew.

Zkittlez Feminized Seeds

One puff of this flavorful strain, and you'll understand why Zkittlez is named after the fruity rainbow candy. Those who try it, say they aren't just tasting the rainbow; they're seeing it as well.

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Another thing that makes Zkittlez a great strain for Illinois is its fast-flowering trait. This indica strain has a short flowering period of 8 to 9 weeks, typically letting you harvest around early October. Under ideal growing conditions, Zkittles can yield 13 to 17 ounces per plant.

Grow Zkittlez by buying feminized seeds in our store, where you can also buy Zkittlez Auto if you want a faster harvest.

Zkittlez cultivar profile

Blue Dream

Blue Dream is a Sativa-dominant strain that loves warm climates with a fair bit of humidity. When growing this strain in Illinois, stick to the southern region’s humid subtropical climate. You would want to provide the best outdoor growing conditions for Blue Dream, as it can consistently yield 21 ounces per plant.

Blue Dream Feminized Seeds

Without a doubt, Blue Dream seeds are one of the most popular marijuana strains in the U.S. Blue Dream gives that 'Cool West Coast Vibe' high sativa-dominant hybrids are known for.

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But with the weather as unpredictable as it is in Illinois, you may need to grow your Blue Dream plants in a greenhouse or grow indoors. You can also grow Blue Dream Auto, which offers a much shorter growing cycle to keep you ahead of Illinois’ erratic climate.

Read our full review of Blue Dream, or buy Blue Dream feminized and autoflower seeds in our store. Download our Plant Care Guide as well to learn how to best treat your plants.

Blue Dream cultivar profile

Conclusion

Growing cannabis, whether as a hobby or a necessity, is easy for anyone to start. Learn how to cultivate like a pro by downloading Robert’s Grow Bible, a free 70-page guide to growing the best marijuana.