Cannabis clones go through two cycles in their lifetime: the vegetative cycle and the flowering cycle. During the vegetative cycle, a plant is doing the majority of its root and foliage growth and should be receiving roughly 18 hours of light and 6 hours of darkness each day. If clones are not kept in the vegetative grow state long enough this can cause something called pre-flowering.
Cannabis plants are photosensitive, meaning they will flower if they receive too much darkness, which can also cause a plant to stress (hermaphrodite: produce seeds). It is important to keep a close eye on the plants in this early stage of life and to watch for signs of heat stress such as drooping or curling leaves. If they do show signs of stress give them a break and move them back to the shade. It is wise to continue to give supplemental lighting through the dark cycle of the day ensuring they do not receive more than 10 hours of darkness. The flowering cycle is the point at which the plant is receiving roughly 12 hours of light and 12 hours of darkness. In an outdoor garden, the plant is naturally triggered to flip to its flowering cycle around the time of the Summer Solstice, which falls between June 20-22nd each year. Ideally, clones should be planted as soon as they get to their home. We recommend preparing the space before picking up your plants. If you do need to store them temporarily before transplanting, the following is suggested: Water your clones with a diluted nutrient solution (400-600 parts per million or ppm) and place them under a low-intensity fluorescent fixture; T8 or T12 bulbs are ideal for this purpose, T5 bulbs are can cause plants to begin “stretching” before you are ready.
Be sure to keep the cubes moist, but be careful not to allow standing water to accumulate in the tray. This will cause the rate of growth to slow, keeping them a manageable size and ensuring that some clones are not dwarfed by larger ones. As your clones begin to stretch, be sure to rearrange them to prevent some clones from being “shaded out,” and transplant them as soon as possible. Photo credit to @m0m_jeens (Instagram) PREPARING FOR TRANSPLANTING. The first step is to prepare the media you are planting the clone into. Some media may require soaking, conditioning, or some other form of preparation. Coco coir blocks, for example, need to be soaked and then broken up. Pre-mixed coco coir substrates are easy to work with and can be forgiving. Popular amendments include organic or synthetic fertilizer, oyster shell meal (for pH buffering), and various substances to improve soil structure. Since it is essential that you have a developed rootball before transplanting into a larger pot, planter box, or direct ground space, it is recommended to first transplant into a 1-gallon pot . After a couple weeks your rootball should be developed, allowing to transplant her into a large vessel. Fill to 1 inch from the tip of pot and gently tamp soil by pressing it down with your hand. This helps ensure that air pockets do not develop; these can dry out your roots and will negatively affect plant health. After tamping, you should have 1 ½ to 2 inches of space between the lip of the pot and the media. This space is important so that you do not overflow the pot while watering. Pro Tip: Some growers reduce “transplant shock” to their clones by soaking them in a vitamin and hormone solution such as Super Thrive. Super Thrive and similar products contain vitamins and hormones that are reported to minimize stress on growing plants. Prepare a batch by mixing one gallon of water with ¼ teaspoon of concentrate. Photo credit to @plantgame_bobross (Instagram) TRANSPLANTING INTO LARGER POT/GROW SPACE. First, dig a small hole in the media about the size of the 1-gallon pot. The top of the cube should be level with the media. If the rockwool cube is exposed too much, it will dry out easily. If the media level is above the cube, it may come into contact with the stem. The stem of the clone should be as vertical as possible. Sometimes this means that the rockwool cube will need to be planted crooked. We find that having a vertical stem leads to superior growing results. Be sure that the bottom and sides of the cube are in good contact with the media. The rockwool cube should be planted so that just the very top of the cube is exposed.
If the cube becomes exposed through watering, gently pack some soil back around it. After several weeks, the clone will be well-rooted, and this will not be an issue. Thorough initial watering helps ensure there are no air pockets or dry spots in your media so that the cube comes into good contact with the water. HARDENING OFF YOUR CLONES – EASING INTO DIRECT LIGHT. Most clones are kept under 24 hours of light in nurseries, whether you are buying from a dispensary or direct from Dark Heart they are likely used to 24 hours of light, but most often the clones are kept under fluorescent or LED lighting and are not yet used to strong or powerful light/heat given off from the sun. Most clones are stored under 24 hours of artificial light in nurseries and dispensaries. When a clone is moved from 24 hours of artificial light directly into intense sunlight, it can experience shock.
You need to introduce your clones to sunlight (after transplant) in a gradual, slow manner. Starting with partial shade and indirect sunlight will be beneficial for the first few days. The partial sun will get them invigorated to grow and the shade will ensure the heat is not so strong that they are overwhelmed and go into shock. For a step by step on how to ease your clones into direct sunlight, read our Hardening Off blog post. For the first week or two, be sure to check the moisture of the actual rockwool cube.