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:
- Harvest your plants during the dark cycle to preserve terpenes and other essential oils at their optimum levels.
- Replace all of the nutrient solution in your hydroponic reservoir every two weeks or more frequently.
- Any yellow or brown leaves should be removed from your plants to prevent pests and mold.
Subject: Spotting Male Plants
From: Lil’ Puff
I just planted a bunch of seeds indoors, and I need to know what the male ones look like. I was told I have to get rid of them soon.
If your seedlings are indoors under at least 18 hours of light per day, you’ve got some time. They won’t begin to truly show their flowers until after you switch the timer on your light so that they get 12 hours of light and 12 hours of darkness per day. Then, within two to three weeks, you’ll see clear signs of sex.
Females will emerge as a teardrop-shaped calyx with a white hair sticking out. This first starts happening at the nodes where the leaves meet the branches. The males will look more like sharp spikes and are noticeably less rounded. As they mature, the spikes will form into what looks like a tiny bunch of green bananas. Get rid of them as soon as you definitely know they are males. Otherwise, these “bananas” will open up and drop pollen all over your flowering females, leaving you with a crop full of relatively worthless seeds instead of the seedless female nuggets you’re hoping for.
Subject: Algae Blooms
About six weeks into flowering, I noticed mold forming on the top of my soil and around the drainage holes of the pots. Visual inspection of the buds shows no signs of mold. There are also several plants only three weeks in with just the nascent formation of hairs and buds. The six-week plants are in full flower and are showing prodigious resin production. I removed the top layer of soil from each pot, but I’m concerned. Is there a way to save my plants?
What I believe you have growing is algae. When light meets water, algae tends to form, diverting some nutrients from their intended target and causing ugly slime buildup. My suggestions are to both cover your top layer of soil with some type of opaque material (white plastic works well) and avoid getting the top inch or so of your soil wet by watering your plant from below. This involves letting your plants sit for a short time in nutrient solution and taking up what the roots need. The top few inches of soil contain few roots and, when kept overly moist, encourage the growth of mold and pests such as fungus gnats.
Subject: The Cure
I’ve grown indoor strains a few times before and cured buds in different ways. Every time I read about how to cure my harvest properly, I see “then put it in the jars and open twice a day.” I’ve been following the rules, but why is it always a glass jar? Is it okay to keep them in plastic containers or coffee cans like those from Lavazza?
The reason we cure in glass jars is because they don’t impart any unwanted flavors into your buds. Plastic containers and coffee cans can change the taste of your buds and make them unpleasant to smoke. Also, they may not be airtight, which can cause the buds to dry out far too quickly. I always recommend using opaque (not see-through) glass jars kept in a cool, dark place. Only open the jars if moisture has built up in them.
Subject: Where to Cut Clones
From: Mr. F.
When taking clones, should the 45-degree cut be made directly under a growing node? Then should I cut the leaf off at that node so there are now multiple surface areas to grow roots from?
Dear Mr. F.,
You are correct! Clones should be cut at a 45-degree angle just below a node. A node is where the leaves meet the main stem. After cutting the clone from your mother plant, remove the leaves that are just above the cut as well. The cut end and the cut area where the leaves were are where the roots will eventually come out, as long as you keep the clone moist, warm and lit with a mild light such as a compact fluorescent.
Some people even scuff the bottom inch or so of the stem of the clone to induce more rooting, but this is a technique for experts only because it’s easy to damage the clone this way. One last thing to remember is to never allow the cut end of your clone to be exposed to air for longer than a few seconds. As soon as you take your cutting and remove the leaves, get the cut end into your rooting medium. If you’re taking a bunch of clones, you can use a cup of water or mild nutrient solution to keep them in until you gently push them into your cloning and growing medium.
Subject: Overwatering Seedlings
From: Mario A.
My question is about starting seeds in larger containers. I tried this once, but I ran into problems with overwatering and the container took a long time to dry out, which led to some mold. How do I manage the water levels when starting seeds in large containers? How do you manage runoff? Do you avoid watering to runoff until the plant is bigger? How long do you avoid runoff, and does salt buildup become an issue?
When growing seedlings in large containers, it’s important not to overwater them. The problems you’re describing are all due to having too much water in your growing medium. Because the roots are so short, you should take care only to water the layers of mix in which they’re prevalent. Watering from below is a great way to get the roots to stretch and seek out water, resulting in more vigorous growth up top. You certainly shouldn’t be watering to runoff early in your plant’s life.
Also, as they grow bigger, never allow your plants to sit in stagnant runoff water. You may experience a little salt buildup, but once the taproot has reached the bottom of your container, you can water to runoff in order to leach some of those salts from your medium. Another way to avoid salt buildup early on is to feed your plants at one quarter or half strength of what’s recommended on the plant-food bottle. Underfeeding is much easier to fix than overfeeding.
You can always start your plants in smaller containers and transplant them as they grow. Be sure they don’t become too root-bound prior to the transplant. Also, be gentle when removing the root-ball and also when placing it into its new container and backfilling with extra soil. The roots will recover much more quickly if you don’t disturb them too much.
Subject: Inside Out
From: Evan H.
I started my plants indoors with an 18/6-hour day/night light cycle, but I need to move them outside at a time when natural daylight will only last 14.5 hours. If I scale back 15 minutes a day until they align with the natural daylight hours, will they experience stress or start flowering? Note that natural daylight hours will then continue to increase again after they get outside for about a month until the solstice.
Your plants should not begin to flower if you follow the regimen you’ve outlined. If you get down to 13 or fewer hours, however, your plants may begin the flowering process and experience some stress as they revert back to the vegetative stage as lighting increases. I recommend using a light outdoors if you can for a few extra hours in order to keep the plants in their vegetative stage. It doesn’t need to be a grow light—any floodlight or even a closely placed fluorescent can do the trick. Supplementing your plants with more light will keep them from flowering until you want them to.
Subject: You Need Some Milk?
From: Tanner Hill
I have a couple of questions regarding adding milk to my water. What kind of bennies could I could gain in a semi-organic grow? Also, does milk indeed kill certain pests, particularly gnats?
I do not recommend adding milk to your nutrient solution. While it does contain some calcium and some vitamins, it’s not an efficient way to deliver them. It’s much better to get yourself an organic Cal-Mag supplement (Suite Leaf Nutrients makes a great one that’s won our STASH Award for “Significant Technological Achievement in Secretive Horticulture”). Some people use diluted milk as a foliar feed to try to thwart powdery mildew (PM), but I don’t find this as effective as other techniques. Milk tends to go rancid quite quickly, attracting bugs and becoming a breeding ground for bacteria, which will cause more problems than it can solve.
Subject: Water Board
From: Corey B.
You recommend testing the water/nutes for PPM and pH before watering soil-grown plants and then testing the runoff for the same thing. What exactly am I looking for? What are the optimum results that should occur?
The measure of acidity or alkalinity, or pH, should be about the same going in as it is coming out. Right around 6.2 or so is perfect for plants grown in soil and soil-less mixes (5.5 for hydroponics). Low or high pH in the runoff water indicates low or high pH levels in your soil mix, which must then be adjusted for roots and plants to thrive.
Before watering, PPM (parts per million) levels will depend on your plants’ stage of life. Seedlings or freshly rooted clones should get 300-500 PPM of nutrients. Healthy vegging plants can handle up to 1,000 PPM and flowering plants up to 1,500. Of course, during the flushing period (the last two weeks of flowering) the PPM should be as low as possible.
The PPM will always be lower in the runoff, and that’s an indication that your roots are absorbing the necessary nutrients they need. If the PPM of your runoff is higher than what you’re pouring in, that could be an indication that your plants have been overfed and you need to flush your grow mix out with plain water to avoid nutrient burn.