I have an indoor growroom and in my recent harvest I found seeds in the buds, but I’m sure there are no male plants in the room. I’ve heard that light leakage can cause plants to become hermaphrodites. Is this true, and if so, do you have any tips for avoiding this?
Cannabis plants are monecious. This means they have the ability to be either male or female. Or in the case of hermaphroditism, they can be both. The reason to make sure there are no males or hermaphrodites in your garden is because male flowers make pollen. When pollen touches the white hairs on a flower, it makes a seed, and seeded weed gives you headaches. Even though there are reasons in nature hermaphroditism could be important, such as continuing the species in case there is no male present, hermaphroditism is generally a bad thing when talking about cannabis plants.
Light poisoning is the most common cause for a normal plant to hermaphrodite.
Light poisoning refers to the flowering night cycle of a plant being unnaturally interrupted with light. The best way to prevent this is to close yourself inside your darkened room during the daylight, and then after allowing a few minutes for your eyes to adjust to the dark, check for any light leaks from covered windows, door jams, etc. Also cover all timer and appliance lights with tape.
Negative stressors can combine with small interruptions of the light cycle to cause hermaphroditism, especially with less-stable, clone-only hybridized strains. When the night cycle is abnormally interrupted, it sends a mixed hormonal signal to the plant. This can cause a full female plant to throw some male flowers. Male flowers are easy to identify, especially when side by side with female flowers. Male flowers look like small bunches of bananas, which will take a week or two to swell before they burst and release their pollen.
Finding a hermaphrodite in your growroom can happen at any stage of the flowering cycle and is indicated by the presence of male flowers growing on the same plant as female flowers. As with all species in nature this can occur in varying degrees. A plant can become slightly or majorly hermaphroditic. In cases where singular male flowers are found between the branch and stalk nodes, you should be diligently removing them as they grow. You must re-inspect the plant top to bottom every few days to be sure pollination and seeding doesn’t occur. If you find male flowers (anthers) actually growing from within the female flowers (buds) the situation is a little more dire. You can still remove all the male anatomy as it appears, but it will be harder to find and much more prevalent. This is a horrible discovery that leads to a tough decision: Should you let the plant live and risk the whole crop being ruined by seeds?
In either case, once hermaphroditism has compromised the safety and purity of your sensimilla, the plant should not be propagated further. Remember, once a hermy, always a hermy. The plant pictured here is in the tenth and what should have been the final week of ripening, but a timer failed and one light stayed on continuously for almost two weeks, causing this vegetative regrowth. Because the light was continuous, the plant made no pollen. This method of re-vegging can be used to save a flowering plant you have no copies of, but be careful, as this may cause some strains to hermaphrodite.
Purposefully causing a plant to hermaphrodite is called selfing. Gibberellic acid or colloidal silver is typically sprayed onto the female plant. This technique is used to make feminized seeds and uses the plant’s ability to be both male and female to force a female plant to produce male flowers. The pollen contained in these male flowers can only produce female seeds. Just keep in mind that feminized plants should not be used for breeding, as they were produced without a true male, making them genetically inferior.
How to Grow Marijuana from Seed
If you’re in a location where cannabis (another term for marijuana; short for the plant cannabis sativa) is illegal, growing it is probably illegal too. Bringing in seeds or cuttings to your location can very well be a felony, and reputable sellers won’t ship to you.
You can probably purchase and grow hemp seeds and plants, which have a negligible amount of THC, but these plants won’t produce the psychoactive effects of plants that contain higher levels of THC. Check with your seller to be certain you’re getting what you think you’re purchasing. If you buy seeds for CBD-only hemp plants by mistake, you can end up being very disappointed post-harvest.
How to acquire seeds or cuttings
You can usually find cannabis seeds for sale at most dispensaries in areas where growing cannabis for personal use is legal. You may also find growers who sell cuttings/clones. You can expect to pay $50 to $100 for a pack of ten seeds. When shopping for seeds or cuttings, read the labels and any other information the manufacturer provides on its website or in its catalog to make sure you’re getting the right seeds or cuttings (the strain) for the plants you want to grow.
One way to get your mitts on some seeds is to collect seeds when you find them in flowers you purchased, or get some from friends if they’re collecting.
- Feminized seeds: Nearly all seeds sold by reputable companies are feminized, but make sure they are. These seeds are specially treated to grow into female plants.
- Auto-flowering or photoperiod: Auto-flowering plants are easier, because they enter the flower stage after a certain number of weeks regardless of the light/dark cycle. If you’re a beginner, seriously consider going with auto-flowering plants.
- Genetic background: If seeds are from a well-established strain, such as O.G. Kush, Bubble Gum, or a cross-breed, the genetic background should be stated.
- Blend: The blend represents the percentage of the three species — sativa, indica, and ruderalis. All auto-flower strains contain some percentage of ruderalis, which is responsible for the auto-flowering nature of the plant.
- Yield indoors: The number of grams of bud per square meter of plant when grown indoors.
- Yield outdoors: The number of grams of bud per plant (after drying) when grown outdoors.
- Plant height indoors: Shorter than when grown outdoors.
- Plant height outdoors: Taller than when grown indoors.
- Time to harvest: Approximate number of weeks after germination the flower should be ready to harvest.
- Potency: Percentages of CBD and THC.
- Effect: The type of experience you can expect when consuming product from the plant.
Know the laws about buying cannabis
- In some European countries, laws prohibit growing cannabis, but seed is legal, which is quite confusing. You’re allowed to buy and eat cannabis seeds because they’re non-psychotropic, but you can’t buy them to grow cannabis. Other countries in Europe, such as Germany, have their own seed laws.
- In Canada, where cannabis is federally legal, seeds can be shipped across provincial lines.
- In the U.S., in some states in which cannabis is legal, you can purchase seeds from some dispensaries or other locations to grow plants as long as you keep them in the state. Other states may bar selling to non-licensed growers. Shipping or transporting seeds across state or international borders is illegal, although a few reputable online seed stores ship to individuals with success.
Cuttings are typically treated in a similar manner as seeds in legalized locations. They may be available from some dispensaries or outlets for pick up or delivery with a fee. They’re prohibited from crossing U.S. state lines or international borders. You can buy individual plants and mix and match strains. Prices vary and are often determined by plant size.
Buy cuttings (clones) only from a reputable source who understands proper back-crossing of strains for stability. Back-crossing involves pollinating a plant with one of its parent plants to promote sexual stability, so that when you have a female it won’t hermaphrodite into a male during flowering.
Both seeds and clones are often able to be purchased from commercial locations already in your state.
In the U.S., transporting any part of the cannabis plant over state lines is illegal. This applies to seeds and clones and, technically, even to tissue samples.
How to germinate cannabis seeds
Germinating seeds requires a dark environment that is around 70 degrees. There are many ways to germinate seeds (in soil, in a wet paper towel, in starter plugs) You can also sow them directly into soil in a garden or container, as long as the soil is light and fluffy, so the roots can easily grow down and the stalk can break through the soil. Plant the seeds about 1/4- to 1/2-inch deep and cover them loosely with soil.
Most importantly, seeds need a moist environment; they won’t germinate if they get too dry. You can use a heat mat to increase the success of germination in colder climates.
How to transplant marijuana plants
When transplanting any plant, whether it started from seed or a clone, handle it gently, being very careful not to damage the roots. Center the plant in the pot, and plant it deep enough to cover the root ball completely in soil. If the plant is root bound, you can gently tease the roots apart to encourage outward growth.
Pack your soil or other grow medium down around the roots well enough to support the plant while new roots grow, but not so tight that the soil restricts outward root growth. Water the soil around the roots.
About This Article
This article is from the book:
About the book authors:
Kim Ronkin Casey has been a communications professional for more than 20 years and recently took a year-long leap into the world of cannabis as the communications manager for one of the leading dispensaries in North America. She now consults for companies in the industry on internal and external communications. Joe Kraynak is a professional writer who has contributed to numerous For Dummies books.
Is it bad to find seeds in your weed?
What does it mean to find seeds in your marijuana buds? Is it something to be worried about?
There’s a seed in my cannabis bud! What does this mean? Is it good or bad?
Sometimes you don’t see the seeds until they fall out of your buds
What causes seeds in buds?
Seedy buds are the result of pollination. What does that mean? Cannabis buds are flowers. Like other flowers, they make seeds when pollinated. Cannabis buds get pollinated when they come into contact with cannabis pollen while the buds are forming.
Seeds happen when pollen gets on the hairs (pistils) of buds as they’re forming. In other words, seeds in weed are caused by pollination.
This bud is full of fat seeds because pollen got on the pistils during bud development.
Pollen typically comes from the pollen sacs of a male cannabis plant. Male plants spray pollen everywhere when their flowers are mature. Sometimes female cannabis plants will produce pollen (known as herming) due to genetics or stress. Any source of pollen, whether the plant is male or female, can pollinate buds in the vicinity and cause seedy buds.
If you’ve found seeds in your buds, it happened while the plant was growing. Either the grower didn’t identify and remove all the male plants before they released pollen, or a herm was involved that self-pollinated or pollinated other buds in the grow area.
Does it mean the weed is bad?
Seeds in your buds aren’t good or bad. They are simply the result of pollination while the buds were growing. A few seeds here and there won’t make much difference in potency, though potency may be lower if the buds are very seedy.
The main problem with seedy weed is that you are getting less smokeable bud for the amount of total mass there. If buds are seedless, you get more bang for your buck. Seedless buds are known as “sinsemilla” (“sin semilla” is Spanish for “without seeds”) and are considered to be the highest quality and most potent type of weed.
Seedy weed is fine to smoke, though you should remove the seeds if possible (they have no THC and will pop if you smoke them). Unless there are tons of seeds, bud potency is unlikely to be affected.
Are “found” seeds good to grow?
I’ve seen some growers get impressive results with bagseed (seeds you find), but results may be hit or miss. Plants can grow in odd ways and the yields or quality may not be as expected.
The biggest problem is that seeds often don’t “breed true” to the buds that they came from. The resulting buds may end up nothing like the buds you found them in.
That is why many growers either stick to clones (which are exactly the same as the “mother” plant) or purchase seeds of a stabilized strain from a trustworthy breeder. This ensures each of the plants will grow the way you expect, and buds more consistently have the smell, yield and potency you expect.
If you’re not sure what strains to get, here are a few recommended favorites. These strains produce excellent weed and are generally easy to grow. Click the links for more information.
– top-shelf looks and smell with classic effects reminiscent of 90s buds but stronger. Easy to grow. – this version is MUCH more potent than regular White Widow. The buds tested between 24-26% THC. Don’t plan to do anything else that day ? – for those who are looking for a face melter. These buds test up to 28% THC and produce buds with quintessentially “American” looks and smell. The mental and physical effects may be too intense for most beginners. is a good choice for commercial growers with high THC up to 30%, big yields, and a short flowering time. is a potent Sativa hybrid with great yields and uplifting unique mental effects is an autoflowering strain that produces photoperiod-quality buds in about 70 days from seed to harvest.
Platinum Cookies is essentially a more potent version of the popular Girl Scout Cookies strain.
How can I tell if it’s a viable seed?
Mature cannabis seeds are typically dark brown or tan (the brown is a coating that can be rubbed off), and relatively hard. Very pale or white seeds usually won’t sprout.
However, I have been surprised to find some very flimsy or pale seeds sprout and produce amazing plants (we aren’t breeding cannabis for hard seeds after all). When in doubt, I highly recommend doing the true test to see if the seed is viable – try to germinate the seed and see if it sprouts !
The best way to tell if a seed is viable is simply to try germinating it
These seeds have germinated
These are all viable cannabis seeds. Every one grew into a healthy plant!