In this stage, your plant will focus ONLY on getting big and strong. Buds and flowers are not part of the plant’s vocabulary yet.
Soilless & Hydroponic growers – If you are growing in any medium besides soil, like a soilless mix or directly in water, you will want to get cannabis nutrients specifically made for hydroponics. Some nutrients are even more specific; for example, Canna Coco is formulated to work best for growing weed in Coco Coir. For hydroponic grows, I highly recommend the General Hydroponics Nutrient Trio – here’s the cannabis-friendly GH trio nutrient schedule I use with my cannabis plants.
At this stage, you can’t tell if one of your cannabis plants is going to be a boy or a girl yet. Wait, why do I care if my plant is a boy or a girl?
Step 6: How to Germinate Cannabis Seeds
For the first 2 weeks of curing, open the jars once a day for several seconds to get fresh air in your jars and release any moisture.
LED grow lights
See another grow under the same 250W light (with autoflowers), and yet another grow we did with 2 plants under a 600W HID grow light a while back. Learn more about HID grow lights.
Step 4: Choose Your Nutrients
Some lights tend to cause more heat problems than others, and we’ll help you find the right lights for your space in Step 2.
If you want to install a lot of bright lights in a small space, you will likely have to install an air conditioner in addition to your exhaust system to make sure you keep your temps in the right range.
You can connect a controller to fans, dehumidifiers, humidifiers, heaters, or air conditioners, and set thresholds whereby each device will power on and off based on your ideal environmental settings. Some units run autonomously, making changes based on set parameters, while others allow you to control each element via an app on a phone, tablet, or computer.
It’s also a good idea to have oscillating fans to provide a constant breeze in your grow room as it will strengthen your plants’ stems, making them stronger and healthier.
Tools to measure temperature and humidity
If you can’t afford both MH and HPS bulbs, start with HPS as they deliver more light per watt. Magnetic ballasts are cheaper than digital ballasts, but run hotter, are less efficient, and harder on your bulbs. Digital ballasts are generally a better option, but are more expensive. Beware of cheap digital ballasts, as they are often not well shielded and can create electromagnetic interference that will affect radio and WiFi signals.
For most first-time gardeners, we recommend buying a quality potting soil that will provide your plants with enough nutrients to get them through most of their growth cycle without having to add many amendments or liquid nutrients. This pre-fertilized soil—often referred to as “super-soil”—that can grow cannabis plants from start to finish without any added nutrients if used correctly.
Soil is the most traditional medium for growing marijuana indoors, as well as the most forgiving, making it a good choice for first-time growers. Any high-quality potting soil will work, as long as it doesn’t contain artificial extended release fertilizer—like Miracle Gro—which is unsuitable for growing good cannabis.