Purple Kush is a pure indica strain, said to be a cross of Hindu Kush and Purple Afghani, that is known for deep purple coloring, a sweet and earthy aroma and a heavy, sedating body high. It is traced to Oakland, California, typically tests at about 18 to 25% THC, and is rated moderate to grow, with a compact plant and an 8 to 9 week flowering time. Details below cover what it is, how it grows, and the tips that research and our strain guide support.
This page is the grower’s companion to our full Purple Kush strain guide, which covers lineage, terpenes and effects in depth. The numbers below come from that guide and from plant-science research, and where the research is silent we say so. Older advice about nitrogen doses and ceiling heights that once appeared on this page was dropped because we could not verify it.
Purple Kush at a Glance
| Trait | What our guide reports |
|---|---|
| Type | Pure indica |
| Lineage | Hindu Kush x Purple Afghani (in most accounts) |
| Origin | Oakland, California; some accounts credit Dark Heart Nursery |
| THC / CBD | About 18 to 25% THC; CBD under 1% |
| Dominant terpenes | Myrcene, beta-caryophyllene, limonene |
| Reported effects | Relaxed, sleepy, happy, heavy body |
| Growing difficulty | Moderate |
| Flowering time | 8 to 9 weeks |
| Yield and height | Medium yield; short to medium plant |
| Best environment | Indoor or greenhouse |
Source: Purple Kush strain guide. Lab values vary by grower and batch.
Where Purple Kush Comes From
Purple Kush is usually described as an Oakland creation, a pure indica made from Hindu Kush and Purple Afghani parents. A more detailed account links it to the Northern California breeder Dark Heart Nursery, but competing origin stories mean nobody can prove which cut is the original. It is sometimes sold as Purple Hindu Kush. Because seed companies and growers have released several versions, buying a seed labeled Purple Kush does not guarantee the Oakland genetics. If you want the strain’s relatives, see Hindu Kush, one of its parents, and Granddaddy Purple, another purple indica.
The warning about names is backed by research. A 2022 study of nearly 90,000 lab-tested flower samples from six states found that products sold under the same strain name vary in terpene profile, and while strain names were more consistent than the indica, sativa and hybrid labels, they were far from ideal (Smith et al., PLoS One, 2022). Expect two Purple Kush jars to differ.
Growing at Home: Washington and Oregon Law
Home growing is legal for adults 21 and older in Oregon, up to 4 plants per household, kept out of public view; see the statute (ORS 475C.305) and our Oregon marijuana laws guide. In Washington, home growing is legal only for registered medical patients. Under RCW 69.51A.210, a patient entered in the state medical cannabis authorization database may grow up to six plants by default, or up to fifteen if a health care professional recommends it. Adults who buy only at retail stores may not grow. See our Washington marijuana laws guide. Cannabis remains illegal under federal law, and local rules and landlord or HOA restrictions can add limits.
Growing Purple Kush: Practical Tips
Choose indoors or a greenhouse
Our guide rates Purple Kush as a compact, early-finishing indoor or greenhouse plant, and warns that its dense flowers can trap moisture. Outdoors in wet Pacific Northwest autumns, plants may develop mold. Humidity is more than a comfort issue. In a 2025 experiment, a plant grown at 78 to 98% relative humidity flowered later and had lower cannabinoid concentrations than one at 37 to 58%, and the literature recommends 40 to 60% relative humidity during flowering (Corredor-Perilla et al., Frontiers in Plant Science, 2025). For a dense-budded plant like this one, that range is a sensible target.
Set the light schedule
Cannabis flowers when days shorten below about 12 hours, so indoor growers switch to 12 hours of light and 12 of dark to start flowers (Backer et al., Frontiers in Plant Science, 2019). One indoor protocol uses 16 hours of light and 8 of dark for vegetative growth (Ijoma et al., J Cannabis Research, 2025). With an 8 to 9 week flowering time, you can plan the harvest date from the day you switch.
Top early to even out the plant
Older advice told growers to pinch the top branches so the plant grows wide as well as tall. That matches what plant scientists describe: removing the main growing tip breaks apical dominance, and the node below produces two new shoots (Ijoma et al., 2025). The review says most growers wait until the plant has about five or six nodes, and that training should stop once flowering begins. Because Purple Kush stays short to medium, you can keep training gentle. See scrogging and trellising and trimming cannabis plants for details.
Make it purple, if you can
Our strain guide notes that the purple color is often attributed to anthocyanin pigments, which appear more with cooler temperatures, and that cooler nights late in flower can bring out the color. A 2025 review supports the general idea: in some plants, moderately cool temperatures of 8 to 15 degrees Celsius improved anthocyanin accumulation, although the effect on cannabinoid yield depended more on maturity (Corredor-Perilla et al., 2025). Cold has limits, so do not chill the room. The same review reports cold stress at 4 degrees damaged plant cells in hemp. The pigment is cosmetic: color does not tell you potency.
Harvest by trichomes
A 2025 review says colas are typically ready when about 60 to 70% of the trichomes have turned amber, with timing depending on the cultivar and the conditions (Ijoma et al., 2025). Check with a magnifier.
What we cannot verify
We found no reliable published numbers for the fertilizer, pH or nitrogen schedules that were once recommended here. Follow the seed company’s instructions and the nutrient maker’s chart. If growth is slow or leaves curl, change one thing at a time and watch the plant.
Using Purple Kush Responsibly
Our guide describes Purple Kush as a heavy indica that people usually save for evening or bedtime. Dry mouth, dry eyes and drowsiness are the main effects, and large doses can leave you groggy. Start with one small inhalation or 2.5 mg in an edible and wait. See our cannabis dosage guide. Common claims about sleep and pain are user reports, not clinical findings. To buy it legally, check menus at licensed stores in Washington and Oregon; menus change weekly.
Purple Kush FAQ
Is Purple Kush indica or sativa?
Pure indica. It is known for strong body relaxation and sedation, though the indica label is a weak predictor of effects. See our sativa and indica guide.
What is Purple Kush a cross of?
Hindu Kush and Purple Afghani, in most accounts.
How strong is Purple Kush?
Typical THC runs about 18 to 25%, with CBD under 1%. Check the lab label.
Why is Purple Kush purple?
Anthocyanin pigments, which can show more with cooler temperatures and some genetics.
How long does Purple Kush take to flower?
About 8 to 9 weeks after the switch to 12/12 light.
Can I grow Purple Kush at home in Washington?
Only registered medical patients may grow in Washington. Oregon adults 21 and older may grow up to 4 plants per household.
For adults 21+ in legal states. General information, not medical advice.
