Explosive growth! That’s a phrase I’ve seen in product marketing for growing marijuana. I define explosive growth as a sudden, positive change in plant performance parameters. These parameters include:

  • Production of new leaves.
  • Thickening of stalks and stems.
  • Height and diameter gain.
  • Budding site development.
  • Early floral development.
  • Bud height, density, and diameter gains.
  • Resin gland development.
  • Scent development.
  • Root development.
  • Overall rate of growth, vigor, and plant health.

There are two co-occurring paths for explosive growth in a properly-tuned marijuana grow room. Understand and coordinate them, and you get bigger harvests at lower costs.

One explosive growth path is the natural growth and maturation timeline genetically encoded in marijuana plants. The other path comes from the precise, savvy application of grow room techniques, materials, feeding programs, grow lights, light cycles, and environmental factors to coincide with, amplify, and accelerate genetic markers. When you understand the natural explosive growth factors, you can exploit them to achieve bigger, more potent buds.

Grow Phase Explosive Growth

Let’s examine the natural explosive growth cycle of marijuana plants. Note that timeline estimates in this explanation are generic; each cannabis strain and individual phenotype you’re growing may slightly vary from this timeline. Also note that this timeline is for regular photoperiod marijuana plants, not for autoflowering cannabis.

The first noticeable explosive growth happens after your seedlings or clones have developed sufficient root mass and leaf sets. For seedlings, it usually occurs 1-3 weeks after germination. For clones, it can occur within a 5-15 days of transferring the clone from its cutting chamber.

The indicator of explosive growth at this marker is a sudden, rapid increase in leaf development, main stalk girth, and vertical height. A plant that had been growing no more than 1/8th to ¼ of an inch per day may suddenly start growing a half inch or more per day. This grow phase growth spurt takes a tiny clone or seedling and turns it into a 2-3 foot tall plant in 3-7 weeks.

In the mostly-invisible world of marijuana roots, a similar growth spurt mirrors what you see aboveground. Marijuana seedlings and clones that have a thin root system with only a handful of branching tendrils in the first couple of weeks of their life suddenly put on massive new growth in root mass density and branching.

Bloom Phase Explosive Growth & Resin Gland Maturation

The next genetically-programmed explosive growth spurt happens with a few days of starting bloom phase. This is the infamous bloom phase stretch, in which plants may double or even triple their height in the first three weeks of bloom phase. The height gain often causes problems in double-ended HID grow rooms, grow tents, grow chambers and any grow op where vertical space is limited. In some marijuana strains, explosive aboveground growth is accompanied by accelerated root growth at the beginning of bloom phase.

During the stretch phase of explosive growth, another type of explosive growth happens along with height gain. This explosive growth is seen when your height-gaining branches begin developing budding sites. The number of sites, along with onset and speed of bud development, are explosive growth factors. Within two weeks of bloom phase start-up, properly-tuned marijuana plants will seem to sprout male or female flowers overnight.

The next explosive growth markers come in early peak bloom, which for most marijuana plants is 2-4 weeks after bloom phase starts. If your marijuana plants are properly fed and cared for and have ideal genetics, you’ll see your buds rapidly putting on weight and resin glands. A bud that didn’t have any noticeable resin glands one day might suddenly have baby resin glands the next day.

Resin glands are the main plant structure where cannabinoids and terpenoids are formed. There are three types of resin glands that develop on cannabis plants. These glands are also known as trichomes. The earliest-developing trichome is called “bulbous.” These are small resin glands that develop on and stay flush on the leaf surface.

Another more numerous type of resin gland is called “capitate-sessile.” It’s larger than the bulbous glands, and has a very short stalk that lifts it slightly off the bud surface.

The third and most well-known cannabis trichome is the capitate-stalked, consisting of a round resinous head on top of a stalk that lifts the gland off the bract. A bract is the smallest leaf in your buds; it’s the leaf most embedded in buds and least likely to be cut off during manicuring.

Elevated capitate-stalked glands are the most visible and most easily seen with magnification and macro photography. They contain the most cannabinoids and terpenoids of any of the three types of marijuana resin glands.

Explosive resin gland size and number growth is most often seen in the middle of peak bloom phase, usually around weeks 4-5 for most marijuana strains, when smaller and shorter bulbous and capitate-sessile glands give way to a growth spurt of a forest of capitate-stalked glands. This sudden, explosive development of capitate-stalked glands is programmed genetically, but can be enhanced or deterred by your marijuana growing techniques and materials.

The final bloom phase explosive growth event isn’t seen in all marijuana strains. It happens in the last 1-2 weeks of peak bloom and/or the first week of late bloom phase. For example, if you were growing a marijuana strain with a 63-day bloom phase, if your strain’s genetics are programmed for explosive late growth, it would take place from approximately day 54 to day 63. As your marijuana plants near the end of bloom phase, the buds stop expanding in size and density and go into a holding pattern while the cannabinoids and terpenoids ripen in the glands.

If you have late bloom explosive growth genetics, your plants will suddenly start adding bracts and resin glands in late bloom. Buds sometimes gain 5-15% more weight and size in little more than a week during their final 7-10 days before flushing and harvest. If you use high-powered bloom phase supplements and a flushing formula, the late growth spurt can continue right up to chop-chop day.

Explosive Growth Reloaded

Standard explosions are chemical reactions, and it’s useful to remember that your marijuana plants grow because of a constantly changing dynamic of chemical reactions fueled by oxygen, carbon, light wavelengths, and the 14 nutrient elements growing cannabis absorbs through its roots.

The rate and efficiency of your plants’ chemical reactions — photosynthesis being the primary driver of all other plant chemistry — are affected by the ratios, quality, application modality and amounts of what your plants receive from their environment and feed program.

Your plants’ internal chemistry and metabolism are also greatly impacted by your outdoor garden or indoor marijuana grow-room environment, water, lighting and other ambient features.

In the majority of grow rooms and outdoor marijuana gardens I’ve studied, the growing protocols, practices and materials are the agricultural equivalent of driving a car with the handbrake on, or not applying enough pressure on the accelerator pedal.

It’s important to understand that chemical reactions drive hydraulic flows that extend from your cannabis plants’ roots and continue all the way to the topmost buds and leaves. Photosynthesis and other metabolic functions drive the hydraulic transport system that creates pressure gradient differentials, resulting in an upward flow of oxygen, moisture, and nutrients into the roots and vertically skyward.

Another important part of botanical chemistry is your growing marijuana plants take in carbon dioxide through their leaves, use it in photosynthesis, then release the photosynthesis byproducts of oxygen and moisture through the leaves. As oxygen and moisture are released through leaves (this process is called transpiration), the plant sucks up more nutrients and moisture through the roots, and on and on in an endless cycle until the plant’s life is over.


Limiters And Enablers To Explosive Growing

Explosive growth is influenced by two major factors: limiters and enablers.

A limiter is any form of input, input parameter or environmental condition that works against the ability of your marijuana plants to give you ultimate performance at the upper limits of physiologic and genetic potential.

An enabler is any input or condition that stimulates your plants to maximum performance. Water is an explosive growth enabler when you’re using reverse osmosis water, provided to your plants in the right amount and at the right time while using pH Perfect hydroponics base nutrients to ensure your plants absorb nutrient elements efficiently. But water is a limiter if you use polluted water, or provide too much or too little water too infrequently or too often.

The same goes for grow-room ambient carbon dioxide levels. Sometimes more doesn’t mean better. Ambient atmospheric levels are at historic highs in our recent geologic epoch, nearing 400 parts per million. These levels create climate change. In your grow room, CO2 gives your plants enough carbon dioxide to fuel normal rates of photosynthesis. If you add CO2 to your grow room to increase ambient levels to 1000 parts per million (ppm) during lights-on cycle, photosynthesis increases as long as all your other inputs and conditions are upgraded and adjusted to take advantage of the increased CO2 levels.

When I reviewed my grow diaries for the past 20 years, the clearest explosive growth incident I found was when I added tank CO2 to my grow-phase grow room, at 1000 ppm. The plants had been gaining an inch in height every 3–5 days. However, when I added the CO2 and made some concurrent adjustments, they started adding an inch in height every 1–3 days! One grow diary entry even told me the plants gained an inch in height in an 18-hour lights-on cycle.

Here’s How You Maximize Explosive Growth:

  • Use root boosters such as beneficial bacteria and fungi, along with Roots Excelurator, starting in grow phase. Stop using Roots Excelurator three weeks into grow phase.
  • Use premium hydroponics base nutrients that balance pH automatically so plants absorb nutrients faster and more efficiently. Look for  “pH Perfect” base nutrients.
  • Add horticultural carbohydrates and Vitamin B to your feed program for the entire bloom phase.
  • Use reverse osmosis water or rainwater, not tap water or polluted well water.
  • Use a P-K (phosphorus and potassium) bloom booster during peak and late bloom.
  • Use a budding stimulator during pre-flowering and early bloom. I use Bud Ignitor and get earlier budding and more budding sites than I would otherwise.
  • Augment grow room air with carbon dioxide (C02) when grow lights are on.
  • Use only the highest quality grow lights.

When you start with excellent cannabis genetics, provide an ideal grow room or outdoor environment, and feed your plants the supplements and premium base nutrients mentioned above, you’ll see explosive growth…leading to faster crop cycles, more harvests per year, and heavier, more potent buds.