Dear Danko: Expert Grow Advice

High Times’ cultivation specialist Danny Danko answers all your burning questions about being the best grower you can be. But first, some quick tips from the expert himself:

  • Root-bound plants in a coco or soilless mix should be transplanted into larger containers.
  • Keep your plant nutrients stored in light- and airtight containers in a cool, dark place instead of under lights in your growroom.
  • Change your clothing and shoes before entering your growroom to avoid bringing in pests.

Subject: Plant Labeling
From: Billy the Kidd

I keep my different strains labeled when I’m growing them, but what do you think is the best way to keep track of them while they’re drying? Keep in mind that I grow over a dozen different plants and smoke a ton of cannabis, so I can’t just remember where I hung everything up and in which order.

Dear Billy,

The best way to keep track is to attach a label to the plant or branch you’re drying. It’s best to move the branches around a bit in your drying space to ensure that everything dries evenly, and attaching a label will help you avoid any confusion later.

Each strain should be cured separately from any others in sealed glass jars. Different strains will require different rates of “burping” or opening the jars to release and replenish the air inside. Denser strains will take longer to cure than wispier ones.

Subject: Burned Tips
From: Jay Farmer

No matter what I do, I always get burned leaf tips! I’m following the instructions on my nutrient bottles (General Hydroponics’ three-part system) to a T, and yet I always have this issue. The buds end up tasting and smoking all right, but I know something is off when I see the tips turning brown and drying up.

Dear Jay,

You are overfeeding your plants. The recommended amounts listed on the labels of nutrient bottles tend to lean toward the maximum your plants can absorb, sometimes leading to slight overfeeding issues such as yours. Most nutrient companies want you to run out of plant food and return to the grow store to buy more.

My advice is to feed at half the rate recommended on the package or bottle unless you see signs of underfeeding. Better to err on the side of caution than to have to deal with the nightmare of overdoing it. You can always add more nutes, but it’s more difficult to remove them in case they over-accumulate. Also, be sure to water with plain pH-balanced water between feedings to give your plants a break. Follow these two simple rules and you’ll never see those dreaded burned tips again.

Subject: Send in the Clones
From: Curious Bones

I sent in a question a few weeks ago about the best way to sex some regular seeds, and although you haven’t answered it yet, I have come to the conclusion, based on another panel discussion on episode No. 49 of your podcast, that taking a cutting and sexing it is the way to go. I have never taken cuttings, and have always grown directly from seed. How long does it take a cutting to root? How soon will that newly rooted cutting flower?

Dear Curious,

In proper conditions, cuttings should root 5-10 days from when they were taken from the mother plant. In order for this to happen, you must keep your cloning chamber warm and humid (around 80°F; and 80 percent humidity). I recommend using a tray with a clear plastic dome under a bank of fluorescent lighting. Cut a hole about the size of a quarter in the clear plastic at either end of the tray to allow for some airflow, and you’ll see roots popping out of the bottom of your medium in a week or so.

If you’re flowering the cutting in order to determine the sex of the mother plant, you can begin flowering it as soon as the clone shows roots. You won’t get much to smoke off of it, but you’ll know the sex of the corresponding plant within a couple of weeks. Tiny yellow spikes that look like small bunches of bananas are a sign of male flowers, while white hairs emerging from a bulbous, teardrop-shaped calyx are indicative of females.

Subject: Slow and Low
From: Unhappy Dwarf

I have had a couple of plants turn out short with tiny leaves. One that I planted around December 1 is only about a foot tall. Another is about 18 inches tall with lots of leaves and branches. It should be 4-5 feet tall by now. Am I causing this, or were the seeds bad? Please help! Should I give up on them?

Dear UD,

Your plants’ lack of growth could be caused by several factors. First and foremost is light. They must receive enough light to perform photosynthesis and create new cells. If you’re growing outdoors, the plants need full, direct sunlight for at least 14 hours a day. Indoors, you need to ensure they’re getting enough lumens from your grow light, which should also be positioned close to the plants.

Your plants could also be suffering from a lack of food. Plants need nutrients to grow, and they eventually use up whatever might be present in their medium. You must provide them with a nutrient solution that will provide the macro- and micronutrients necessary for healthy growth.

The third factor is genetics. It doesn’t sound like you’re familiar with the strains you planted, and so they could have bunk genes. Seeds pulled out of a baggie of buds don’t tend to perform nearly as satisfactorily as well-bred F1 hybrids with hybrid vigor.

You don’t have to give up on your plants, but you should definitely change their situation by adding light and nutrients. If that doesn’t help, then you’ll know it was the seeds themselves that are to blame and you can move on to better genetics in the future.

Subject: Planting Seeds
From: Thomas G.

Should I germinate my seeds before I plant them? I’ve heard differing opinions, and I’d like to know the best way to get them started for optimal growth.

Dear Thomas,

Some people choose to use the moist-paper-towel method to germinate their seeds, but I recommend just sowing them directly into the medium you plan to grow in. This reduces any stress the seedling might suffer during the transplanting process and secures the young plant firmly into your chosen mix. It’s important not to plant too deeply (a quarter-inch deep is perfect) and to keep the medium moist and warm for the best germination success rate.

There’s nothing inherently wrong with using a moist paper towel, though, as long as you’re gentle with the emerging lap root and you don’t let it grow too long before planting. I prefer simply to start the plant in its own medium, which reduces the likelihood of damaging the tender young roots and shoots. Additionally, always keep your grow light close enough to your seedling so that it won’t stretch too much and become long and lanky.

Subject: Vegging Again
From: Gary

I’ve heard some very interesting things about growing that make me wonder. A friend of a friend claims she has clipped buds from her mature plant and returned it to an 18/6-hour day/night light cycle, and it started growing again. Have you ever heard about this? Is it a bunch of fertilizer?

Dear Gary,

Yes, it is absolutely possible to do this. It’s called re-vegging. After you’ve harvested most of your plant, leave some fan leaves on a few branches and place it under a vegging light cycle, and you’ll see new leaves and branches begin to develop after a week or two. This is a particularly good technique if you are trying to save a certain strain and the plant is your only genetic connection to it. Once enough leaves and branches have formed, take a clone from your re-vegged plant and root it in order to keep that strain in your motherplant library.

I don’t recommend re-vegging in order to re-flower the plant, however. The law of diminishing returns is at play, and while you will get some buds out of the plant, your yield won’t be worth the effort and time spent on accomplishing the task. You’re always better off starting with a fresh seedling or rooted clone than with a re-vegged plant. So consider re-vegging as a last resort to save particular genetic material, and not as a way to get a second harvest from the same plant.

Subject: Curled Leaves
From: Barry F.

Can [you] tell me why my leaves are curling under on my indoor pot plants?

Dear Barry,

There are several things that might be causing your leaves to curl under, but the most probable is water stress. Most likely, you are overwatering your plants. The other possibilities are over-fertilization, high temperatures or nutrient lockout caused by pH variation. Check your temperature, nutrient and pH levels; if all of them are within the proper parameters, then water stress is the likely culprit. Let your plants’ medium dry out between waterings and the symptoms should go away.

One last thing I should mention is that there are also plant viruses that cause leaves to curl under, but I’d have to see a photo to correctly diagnose that malady.

Subject: Bud Boosters
From: Glen J.

I have a few plants outside. The buds are really small and it’s starting to get cold. Is there any way to boost bud production before I’m forced to cut them due to frost?

Dear Glen,

While there is no way to get buds to grow any faster than they are genetically disposed to grow, there are a couple of things you can do to still harvest a decent crop. First, you can utilize some sort of greenhouse structure in order to extend your growing season.

A hoop house or small greenhouse can retain heat in cold-weather conditions and keep your plants safe from frost for at least a few weeks before it gets too cold. If the greenhouse is heated or attached to a heated residence, you can continue growing well into the winter.

You should also consider bringing your plants indoors to finish growing under grow lights. If the plants are in the ground, carefully dig them up, trying to avoid damaging the root system, and put them into containers that have drainage holes.

Send your cannabis-cultivation questions
to deardanko@hightimes.com.

This feature was published in the May, 2019 issue of High Times magazine. Subscribe right here.