Welcome to Leafly’s cannabis homegrow! Watch as our writer Johanna Silver grows a set of marijuana plants from seed to harvest in her backyard. Follow #Leaflyhomegrow on Instagram, Twitter, and Facebook.
Also, check out her book, Growing Weed in the Garden: A No-Fuss, Seed-to-Stash Guide to Outdoor Cannabis Cultivation.
Weed flowering and plant anatomy
Today, we’re going to talk about flowering. Finally, what you’ve been waiting for. The flowers, they are here.
In the garden, we’ve got all these unpollinated female flowers, and they are just trying to get pollinated. They’re making themselves as attractive as possible to male pollen that floats in the wind. They’re getting stickier and stickier, just trying to get covered in pollen.
But with no males, ain’t going to happen, so you’re going to have all these super sexually frustrated, sticky flowers that eventually give up and die. Except, we’re going to kill them before they killed themselves.
First off, fan leaves. Don’t worry if these are starting to turn yellow and fall off. The plant is much more focused on flower production now. It gives up on the leaves, and you should too. Just relax, and it’s fine to take off the dead ones.
Here are the flowers. I know it’s strange to call them flowers. They don’t really resemble any other flower in the garden. Densely packed together, we call them colas.
The leaves that gets super packed in there are referred to as sugar leaves, named for the heavy dusting of trichomes. Those trichomes, the resinous glands, pack all the terpenes and cannabinoids, the goodies of the plant, and they basically cover every part of the flower.
Calyxes are the tear-shaped parts that contain all the reproductive stuff, including the stigma, the hair-like things that will ultimately start turning amber and help tell you when the flowers (buds) are ripe.
That’s sort of it. The plants are going to get weirder and weirder from here on out: The colas start extending upward, and the plant takes on a weirder shape.
You’ll also probably start smelling them from farther and farther away. Don’t be surprised if your neighbors start peeking over the fence or if your husband says you need to get a new career.
Again, there’s not much to do. I don’t prune anymore, because you’re doing nothing except removing flowers, and I don’t fertilize anymore. I just let the plant do what it’s going to do, which is make really pretty flowers until I kill it (at harvest).
Troubleshooting common weed problems
Johanna here, still in my backyard in Berkeley, California, still growing weed. We are well into summer. Some flowers are blooming. Everything’s growing. Weed may be flowering. I’ve got some pistils shooting up. Don’t worry if you don’t notice anything yet, it’s coming, I promise.
OK, this is the slow part of growing. There’s quite honestly not a ton to do:
- Keep them watered
- Prune out any branches that will never reach the light of day
- Maybe fertilize, if you’re into that—I’m not, and too much can actually cause problems with disease.
We’re going to talk about the dark side. Everything that could go wrong.
Common weed problems
There are a bajillion potential pests, and almost all of them can be minimized if you just give the plant what it wants from the start:
- Enough sunshine
- Plenty of air flow
- Right amount of water (not too much)
Example: marks from spider mites. Earlier, this pot was closer to the wall. Airflow was a little bit limited, and instead of panicking, I just moved the whole thing out a few inches from the wall to increase the airflow.
Don’t assume that drastic measures need to be taken. The idea of integrated pest management is helpful: The approach that you take the time to make a proper diagnosis, then use the least invasive solution first to see if that helps (rather than just reaching for some giant jug of chemicals).
Up first, bud rot, aka gray mold, aka botrytis. Outdoors there are lots of butterflies and moths, like the stupid white cabbage moth. In caterpillar form, they lay their eggs in the buds. The caterpillars hatch and grow in the buds. They shit in those buds. And when it rains, which it does around here, right before the crop has finished, that shit turns into mold. Voilà, you’ve got botrytis in those buds.
In years past, when I see a bud that has a little bit of gray mold on it, I just snip it out and toss it. But I realize that you, might give a shit about how much weed you harvest. So let’s talk about some solutions.
BT, or Bacillus thuringiensis, has been around since the 1920s. It’s one of the safest biopesticides around. It’s a species of bacteria that lives in the soil. It is very toxic to caterpillars and not at all toxic to you. Don’t panic, it’s organic.
Take preventative measures, not reactionary.
When buds first start to set, around end of July, spray once a week with BT, all the way through August, until those pretty little hairs come out of the flower or any time after there’s a big rain.
And if you get hella lazy, you can just cut out rotten buds at harvest time.
Powdery mildew is a super common fungus that shows up on your plants’ leaves looking like white powder. I know it mostly from growing cucurbits—the squash family—squash, cukes, pumpkin, zucchini, watermelon, any of that stuff, super common.
With weed, powdery mildew can seep into those flowers. And then come use time, you are ingesting or smoking fungus, which is not ideal.
Best advice: prevention. Full sun, plenty of airflow, water the soil level and not the leaves.
If you do start to see some powder on those leaves, you’ve got a couple of options. If you feel like spending a little cash, get yourself a bottle of Serenade, another Bacillus-based biopesticide that’s super safe and been around a long time.
Or go the DIY route:
- 1 TBSP baking soda
- 1/2 tsp non-detergent liquid soap (like Dr. Bronner’s)
- 1 gallon water
Spray that once a week.
A really good idea (it’s my buddy Jamal’s only rule and he’s a pro grower): Don’t plant anything from the squash or cucurbits family next to your cannabis since everything from that family is super susceptible to powdery mildew. It is a disaster waiting to happen.
How to prune your weed plants
Today, we are going to learn how to prune plants, which means making cuts, which means I’m going to cut the plant, and you’re going to get really uncomfortable. But it’s going to be OK, I promise.
Indoors, they compensate for using top-down static light that doesn’t move, so they have to do all sorts of crazy shit with pruning to get the light to hit all the branches.
You don’t have to do any of that outdoors. Why? The sun. It moves across the sky all day, hitting different parts of the branches, different leaves, different flowers. You don’t have to do much at all.
Now, left un-pruned, your weed will grow into the shape of a Christmas tree with one giant cola (which is the weed word for flower bud). That sounds like the coolest thing in the world, but in practice, is not. All that dense, moist growth, with no light in there, is just a recipe for mold, disease, disaster. It will be a nightmare to dry and cure evenly, which is the whole goal with weed.
So you’ve got to make some cuts. The question: which? We’re going to keep it crazy simple.
Making the cut
You’re going to count one, two, three sets of leaves, and cut.
You can do this in the ground, or you can do it while it’s in a pot, it doesn’t matter.
I’ve been growing this beautiful plant for 10 weeks, and I’m going to cut right above where the next set of branches are growing.
Why topping is important
Why did I just cut the whole top off this beautiful plant? Well, topping the plant, or cutting off the terminal bud, tells the plant to instead put all of its energy into growing lateral branches and grow a lot more bushy and form a lot more reasonable and more manageable sized buds, putting you in a lot better shape come harvest time.
If you want to be done there, be done.
If you want to do a little more, wait until each of the remaining branches grow three sets of leaves, and cut it again. That will encourage more branches and more reasonable sized buds.
With the cut-off branch, you can do so many things:
- Throw it in the compost pile
- Use it in a flower arrangement
- Juice the leaves
- Get a flower press and do some botanical crafting
- Whole lot of things except get high
Transplanting your weed plants
I’m going to show you how to transplant your weed from wherever it’s been growing straight into the ground where it’ll grow big and tall and beautiful, until you kill it (at harvest).
When to transplant
How do you know when they’re ready?
- I’ve already sexed my plants, so I know that I’m going to only be growing females from here on out
- It’s nice and warm—evening temperatures are staying above 55°F, which for summer annuals is the total magic number
- It’s before the Summer Solstice, so there’s still plenty of sunshine going on and these babies still have plenty of time to pack on vegetative growth, getting real nice and big before they start flowering.
The best time to plant any transplant is on an overcast day or in the evening—the plant will have some time to acclimate to its new home before getting blasted by sunlight the next day, and it helps minimize shock.
How to transplant
Preparing the hole:
- Nothing is dry: The ground and container have both been given a splash so nothing goes into shock
- Check on it every day for the next week because it’s a brand new baby
- It only needs to be watered when the soil is dry two inches down: Best way to figure out, stick your finger down two inches—if it’s dry, time to water
- When digging the hole, make sure it’s approximately twice as wide and deep as the container itself, to make sure the roots have plenty of new uncompacted soil to grow into to thrive and prosper
- Add compost (rake it smooth before digging)
- Add two amendments:
- Bat guano—high in nitrogen; will help leafy vegetative growth
- Bone meal—high in phosphorus; will help it flower later on
- Take the plant out of its container, tip it upside down, take off the container (admire those beautiful white roots, and don’t mess with them)
- Put the root ball gently into the hole, making sure the soil level is flush with the soil level of its new hole
- Backfill with soil—just scoot back all that dirt and fill the hole back up
- (optional): I add a sturdy tomato cage for trellising—as the plant grows, she will get real big and get real heavy flowers; I want to make sure branches don’t snap later in the season if there’s a rainstorm or really windy night
Having some amount of structural support will go a long way, and for me, a tomato cage does just the trick. I put it in at planting time so as not to disturb the roots later.
Don’t forget the last step: Never forget to put your label back in.
Sexing your weed plants
Cannabis plants are dioecious, meaning males and females are on separate plants—that is super rare in the plant world. This is the most fun part of the process, sexing the plants: learning to tell the difference between those males and females.
When you buy weed from a dispensary, you are always buying female flowers—ideally unpollinated female flowers. That is how you get beautiful bud without seeds. So long as you’re after a crop of unpollinated female flowers, you’ve got to learn to tell the difference and you’ve got to chuck the males.
Of course, you can hang on to a male if you’re looking to try your hand at backyard breeding, maybe for some seeds for next year’s crop (but it’s very difficult). There is no guarantee they’re going to come out anything like either one of their parents.
So just know that if you hang onto a male plant, you are going to pollinate your entire crop, probably your neighbor’s, and your neighbor’s, neighbor’s crop. You’ll have weed full of seeds.
Identifying weed sex organs
Flowering won’t kick off in earnest until after the Summer Solstice, but with plants just over two months, you can most certainly sex them from their pre-flower.
Helpful tools: magnifying glass or a jeweler’s loupe.
When you’re growing outside, they will be ready to sex around 8-10 weeks.
- Find a node (between the stem and the branch—it’s like the armpit of the plant)
- There you’ll find a flap that looks like a flag, and that’s called a stipule
- Peel back the stipule, right where the next branch is starting to grow out, and you’ll find a sex organ
Males = Balls
Females = Round thing that’s not quite a ball and has a white hair (that white hair is a pistil)
If you think you see all balls, or you can’t quite tell, give it another week or so. Female sex organs are round, but they don’t scream “ball”—they look like something’s about to grow from them. In another week’s time, you’re likely going to see a hair or two.
Not everything is going to be a male—there’s no way you started all your seeds and they’re all males.
If you want to keep a male, give it a snip, strip it of its leaves, and put it in a glass jar inside. Grow it like you would a cutting or a flower and it will continue to grow.
When the pollen is released, it won’t get everywhere so long as it’s not near an open window. Once released, you can scoop up a little and selectively pollinate some flowers that you’ve got outside for seeds next year. Be careful not to pollinate your entire crop!
How to pot up your weed seedlings
Hey, this is Johanna and we’re back talking weed in my backyard, and we are going to pot up the babies into their next home.
I am potting these from their 4-inch containers where I sprouted them into gallon-size containers, where they will live for a little bit while longer.
You know your plants are ready for a bigger home when they’ve grown past the seed leaves—the cotyledons—and they’ve sprouted a few sets of their first true leaves. You want them to be looking healthy, not stressed out, so they can handle being moved to a new home.
These are about five inches tall. That’s great. You just want to have a few sets of those true leaves.
To transplant your weed:
- Give the weed seedlings a splash of water
- Use fresh potting soil—always fresh, do not reuse potting soil
- Everything should be moist, including potting soil—it doesn’t need to be dripping wet, but you want to minimize the shock for the plants
- Fill up the gallon with potting soil—you can sink the 4-incher in there to see how much to fill in advance (you want to submerge the cotyledons and even go a little deeper)
- Hold the plant upside-down in your hand
- Gently take off the 4-inch container
- Place it in the middle of the container
- Fill in the rest of the gallon with potting soil
I like to give mine a little shake to get them level and a little pat because potting soil is pretty fluffy. It will settle a bit. You don’t need to tamp it down with your hand.
I’ve left a little bit of a gap, about an inch at the most, for water to have a place to drain.
Important: Label goes back into the plant.
Give the new container a sprinkling of water to help everything feel real good in its new home. Keep them in the shade the rest of the day and throw them back in the sun first thing in the morning.
How to pop (germinate) your weed seeds
Wondering when you should start your weed seeds? Use the Farmer’s Almanac to find out dates for starting tomato seeds in your region and use those.
Before you get started, you will need:
- 4-inch containers (left over from whatever other stuff you’ve grown in your garden)
- Tray (for moving them around)
- Fresh potting soil—important: it says “potting” on the bag and you haven’t used it to grow other stuff
- Optional: Sharpie Extreme (it’s permanent and weatherproof)
- Weed seeds
I’m growing three cultivars this year:
- Sweet Annie (Humboldt Seed Company)—1:1 THC:CBD, also a beautiful plant
- Freakshow (Humboldt Seed Company)—a crazy cannabis leaf that does not look like any other weed leaf
- Cherry Pie x Chem Lemon—given to me by my buddy, Jamal (he told me it was a beautiful plant and I like pretty things)
The legal limit in my area is six plants. I’m only looking to grow three. So I am going to pop a few seeds of each cultivar and trust that one or two is a lady.
Make sure you know the laws in your area.
How to germinate weed seeds
- Fill up 4-inchers with fresh potting soil. Fresh, has not been used for other things
- Write labels. I’ve made the mistake of only writing one label for a row—inevitably, you mess yourself up and you don’t know what your plants are
- Place labels in containers.
- Plant one seed in each container.
- Rule of thumb: Plant a seed twice as deep as the seed is wide
- Make a little indentation in the soil with your finger, drop the seed in, and pinch it shut
- Give the pot a little shake to make it level
- Give it a gentle splash of water either with a watering can or with the shower setting on a hose nozzle—make sure they’re drenched, but don’t blast the seeds away
- Optional: Put them in a small greenhouse to keep them safe and warm
All you have to do from there is make sure the little containers are watered thoroughly for the next few days. You want to see water coming out the bottom and see that they’re thoroughly wet. They don’t need to be soggy, but you don’t want them to dry out.
They can germinate anywhere between 3-12 days.
In no time, you’ll see little green sprouts pop their way up.
How to pick a spot to grow weed
What’s up fellow weed growers!
I’m Johanna, coming to you from my Berkeley, California backyard. I grow fruit, veggies, herbs, cut flowers, and yeah, weed. I grow weed entirely outdoors, in the sunshine, no fancy equipment, not a lot of fuss. And I’ve actually found that information for that type of a grower is incredibly hard to come by. So I’m here to help show you how to do it.
And what’s the very first thing you need to do when growing weed? Find a spot to grow it.
What to look for when picking a spot to grow weed
Full sun. In the outdoor world of gardening, full sun means at least six hours of direct sunlight a day. Just six to eight hours of direct sunlight and nature is going to do the rest. Morning sun is always a little bit gentler and more loving than afternoon sun.
Super good soil. When you’re gardening you’re actually cultivating soil more than you’re cultivating the plant. So you want some nicely amended, well draining, yummy soil.
Plenty of room. Weed is pretty variable in size so allot five to six feet of width.
Other considerations: If you live somewhere crazy windy, you’re going to want to plant them with a barrier—either a wall or other plants.
Privacy. In many locations, it’s only legal to grow weed behind super tall fences. You also don’t want your neighbors stealing your stuff.
Access to water is absolutely key. Plants need water to grow.
Here are three spots I’m going to grow in my backyard:
- Existing veggie bed—Looks nice, has drip irrigation, full sun in the afternoon. I don’t love that the soil has been cultivated a lot.
- The graves—They get incredible full sun all day long and also have incredible soil—super juicy, full of worms (the grass has acted as a cover crop for the last three years). Not ideal: sprinkler heads are going to make things a little wet.
- A container—A good choice if you don’t have access to in-ground planting. It should be 5 gallon minimum, 15 gallon ideal; use fresh potting soil. I can make a really cute little scene with a couple pots, some flowers, and I feel like an utter badass that a big weed plant is the main attraction.