The HIGH TIMES Spring Pot Planting Guide

Heavy yields of big buds in the fall are the result of proper planning and planting in the spring. Danny Danko breaks down the basics of mastering these early stages in order to harvest more down the road.

Start Early Now, Harvest Heavy Later

As winter fades away, our thoughts turn to renewal. Spring always brings with it hopes for the future: The ground begins to warm, and tender young shoots emerge from the soil. But these plants are perennials, destined to grow out year after year without toil, while our beloved cannabis is an annual and must be planted each spring in order to grow bigger throughout its vegetative stage in the summer and then enter its flowering stage in the fall.

The best way to ensure bigger plants, and thus greater harvests, is to plant seedlings or clones indoors under lights during the winter, before they can survive outdoors. This means planning ahead and creating a vegetative space attuned to healthy, happy pot plants. You’ll need a warm (over 70°F) and humid (around 50 percent relative humidity) space, clean and well lit.

We highly recommend using metal halide (MH) lights for the strongest growth and best results during the vegetative stage. The wattage you use will depend on the size of your space, but a good rule of thumb is that a 2′ x 2′ space can be covered by a 250-watt bulb and reflector, while a 3′ x 3′ space would need 400 watts and a space or larger can handle a 1,000-watt system. High-pressure sodium (HPS) lamps, light-emitting diode (LED) technology or fluorescents will work for this purpose as well, but the MH spectrum is ideal for vegetative growth and will keep internodes short and plants bushy.

The biggest outdoor plants start their lives indoors as early as December and, by the time they go outside after the threat of frost has receded (which varies depending on where you live), they’re three feet tall or bigger, with thick stalks and many branches. This is the only way to achieve the massive 10-pound monsters you see in the photos.

Planting Seeds

There are several ways to properly germinate seeds. Some people place them between two wet paper towels and wait until they start popping open before gently putting them into the growing medium. The important thing to remember when using this technique is not to let the emerging taproot get too long before doing this (and also to always place the seedling into the medium with the taproot pointing down).

The easiest and most fail-safe way to sow seeds is directly into your medium of choice. Poke a hole in your moistened soil mix (or coco, rockwool cube, etc.) and drop the seed in about one-quarter to half an inch deep. Cover the seed with mix, keep the area moist and warm, and within a couple of days, you should see a tiny green shoot emerging from the soil. Immediately place it under adequate grow lighting – preferably a high-intensity discharge (HID) light – and your seedling will stay strong without stretching.

Plants grown from seeds tend to grow more vigorously than those grown from clones. The hybrid vigor  particular to seeds from the F1 (or first filial) generation creates monster bushes that grow rapidly as long as they receive plenty of fertilizer and light. Many outdoor growers prefer to start from seed for this reason.

Rooting Clones

The best way to ensure uniform growth (important for indoor growers) and strain consistency is to root clones taken from mother plants and then grow them out. Clones are pieces that have been cut from plants in order to induce new roots to shoot out from the cut ends. The cuttings thus become smaller exact replicas of the mother plant, maintaining the sex (female), strain genetics and growth characteristics. This is how commercial growers end up with uniform plants that perform the same, growing a level canopy and taking advantage of all available light without shading each other out.

Clones are cut from vegetating mother plants using a sharp blade. Cut on a diagonal just below a node, leaving at least three sets of intact leaves on the cutting you’ve taken. Remove the lowest leaves (the ones coming out of the node that you cut below) and immediately place the cut end into your moistened medium of choice.

Temperature and humidity are very important factors for inducing roots to grow from the cut ends, so use a plastic tray with a heat mat underneath and a clear plastic dome over it for the best results. Within a week or so, you should see roots emerging from the bottom of your plugs or cubes and new growth from the plant tips. You are now ready to transplant your rooted clone into the growing medium and begin the all-important vegetative stage.

Maintaining Mother Plants

In order to get healthy clones, you must have healthy mother plants. These are female plants in their vegetative stage with green leaves and new shoots forming constantly. Mother plants should preferably be kept under MH lights, but compact fluorescents will work in a pinch.

The best way to acquire a mother plant is to grow one out from seed. But the only way to determine the sex of the plant without flowering it (unless it’s grown from feminized seeds) is to root a cutting from the plant and then flower out the clone. In this scenario, the mother plant remains under 18 to 20 hours of light per day, while the rooted clone is placed in a separate flowering area under a 12-hours-on/12-hours-off light schedule.

Within two weeks or so, you’ll see signs of sex on the clone, but it’s best to continue flowering it out completely in order to ensure that it’s not a hermaphrodite. Any signs of male genitalia on your flowering clone mean you must get rid of the corresponding mother plant or risk seeding your crops. Male flowers are easy to spot: They look like tiny yellow bananas sticking out from the buds.

If the clone is female, you’ll know the corresponding mother plant is female as well. At the same time, since the mother plant itself hasn’t been flowered, this means the plant is stress free, since its light schedule has never been interrupted. Mother plants grown from already flowered and then reversed plants tend to produce stressed-out cuttings, while mother plants that have stayed in their vegetative stage give off only strong, healthy clones.

Feed mother plants a mild vegetative nutrient solution and always monitor them for overfeeding. Because they live much longer lives, mother plants are at greater risk of deficiencies, nutrient overloads and pH imbalances. Give them plain pH-balanced water between feedings and you’ll find that they stay much healthier and happier.

The Vegetative Stage

After a seedling or rooted clone has begun to form its first few sets of new leaves, it enters the vegetative stage of growth, when more leaves form and new shoots become branches. Care must be taken to provide the plants with a nutrient solution high in nitrogen, since this is the macronutrient that assists in the formation of green foliage.

On the N-P-K scale, the nitrogen (N) level is given first, followed by phosphorus (P) and potassium (K). During the vegetative stage, use a fertilizer with a high number at the beginning of the N-P-K ratio listed on the package or bottle (e.g., 5-1-1). Healthy green leaves and new growth are signs that the nitrogen levels are good, but yellow leaves point to a deficiency. Conversely, burned leaf tips indicate an overabundance of nitrogen and other nutrients, so scale back on the feedings and flush your plants with plain water if you see the leaf tips start to get crispy.

Keep in mind that the larger the hole in which your plant is growing, the bigger the plant will eventually be. If you’re growing in containers, use nothing smaller than five-gallon pots in order to yield plants that are decently sized. Larger pots, such as 35-gallon tubs, are ideal both indoors and out if you plan to have a vegetative stage lasting longer than a month. (Outside, this period is determined by the sun, but indoors, you can control when the flowering stage is triggered by cutting back the light to 12 hours on/12 hours off.)

Root systems with plenty of room to flourish produce much larger plants than root-bound ones. Outdoors, you can dig out a 3′ x 3′ hole and be sure to dig deep as well. Fill the hole with store-bought planting mix and add any amendments you’ll be using at this time. We suggest organic ones such as seabird guano, greensand and compost. Some people like to use polymer crystals to cut down on watering, since the crystals soak up and store liquid and release it slowly to the roots. They’re a great addition to your soil mix, especially if you don’t have everyday access to your grow site.


The vegetative stage is the time for pruning in order to achieve more branches and bigger plants. Once a plant has three or more nodes, it’s time to start the pruning process. It can be as simple as trimming the tops off growing shoots in order to increase the amount of future branches, but there are several different ways to prune selectively.

Some growers train the branches by weighing or tying them down. This increases the surface area that the light can reach and turns secondary branches into main tops. Bushier plants produce much more pot than Christmas-tree-style plants with one main cola.

A sinker (such as those used in fishing) works great to weigh down a main branch without having to cut it. Once the main branch sags below the lower branches, the plant signals those branches that they are no longer subordinate to a main top and can each become a dominant branch – thus raising your future harvests significantly.

Smart growers introduce a trellising system during the vegetative stage in order to spread their plants’ branches wide. There are many different types of trellis, from chicken wire to ropes, but what they all have in common is spreading the canopy. Branches tucked underneath a horizontal trellis will produce many more bud sites than branches growing upward, so be sure to use one form of trellis or another to get the most out of each plant.

Foliar Feeding

The early stages of growth are also the best time for foliar feeding – spraying the leaves of your plants with water or a mild nutrient solution such as aerated compost tea or liquid kelp. Plants can absorb trace elements directly through their stomata, making foliar feeding a great way to get those elements where they are needed.

Foliar feeding is best done in the morning, before the sun reaches its highest point, to avoid burning the leaves or branches; in the middle of the day, the hot sun and bright light can also force the stomata to close up. You should also avoid spraying close to nighttime or the start of the dark cycle, because the liquid won’t have time to be absorbed and will linger on the leaves, creating the perfect situation for mold to develop.

Foliar feeding has the added benefit of cleaning the leaves of any dust that could be hindering their ability to take in light. It also discourages most pests from making a permanent home out of your plants. Be sure to spray both the tops and undersides of the leaves for full absorption. Never foliar-feed plants indoors without first protecting your light source from the mist, and cease foliar feeding at about two weeks into flowering to avoid bud rot.

Onward Into Flower
Now that you’ve gotten them off to a good start, your plants are ready to enter the flowering stage. As you see signs of bud formation, shift over to a nutrient solution with more P and K (phosphorous and potassium). The plants you’ve painstakingly built into big vegetative bushes will soon transform into monster-sized marijuana trees. Enjoy!

RELATED: How to Grow Huge Outdoor Pot Plants Next Season

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