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Kryptonite Soil FAQs



Do I need to add anything to Kryptonite? It can be as simple as the package says “JUST ADD WATER”. This soil is designed to be nutrient-dense and geared to provide microbial life with everything it needs to help deliver the right food at the right time to the plant. We recommend that for your first few grows you don’t add anything. We’d rather you focus on enhancing your other cultivation practices like watering, topping (i.e., pinching off the apical meristem); pruning, monitoring your environmental conditions. Then, it’s time to bring out that creative side in which you may wish to trial topdressing other ingredients or plant teas.

How much water do I add? Watering a plant is truly a skill. Too much and you will create a soil environment with little oxygen for the roots (and the microbes) and most likely a nice home for such pests like fungus gnats. Too little and the plant will be unable to take up nutrients and demonstrate signs of wilting. The amount of water you add is very linked to the environmental conditions you have in your growth. Typically, in flowering, if you have a leaf temperature near 28C and relative humidity at 55%, a cannabis plant may consume up to 2L of water per day. Read more below about top or bottom watering.

Ideal room temperature? The cannabis plant is heat-loving, but not excessive heat (never above 30C unless you can supplement the plant with increased water, CO2, and nutrients). The temperatures also vary through the life cycle of the plant. Typically, in the vegetative phase a leaf temperature during lights-on can be as high as 27C and during lights off can dip down to 24C. In flowering, temperatures can get as high as 29C, especially if you are supplementing with increased levels of CO2 (cooler temperatures and higher humidity may be required if you have spider mites). Your lights on and lights-off temperatures shouldn’t vary too much (stay within 5C) otherwise you may stress the plant and diseases may develop. A nice trick to help bring out the colours in the leaves and pistils is to lower the temperatures in the last 7 to 10d before harvest (down to 20C). This mimics the autumn temperatures and increases certain medicinal compounds called flavonoids.

What type of water should I use, tap, distilled etc.? We usually recommend ‘potable’ water – so essentially free from pathogens and heavy metals. Kryptonite has great buffering capacity so water at a pH of 5.5 to 7.5 will show no deficiencies in nutrients like iron, zinc, phosphorus, and manganese. Chlorinated tap water should sit out to help reduce some of the chlorine and when growing indoors water temperature should be around 15 to 18C. Another tip to help bring out terpenes and flavonoids is that you can water with very cold water (around 4C) the last 7 to 10d before harvest.

Can I top dress with Kryptonite? At times we end up growing a bigger plant than we expected or our environmental conditions aren’t just right and we need to add extra nutrients. If you are top watering you can add some extra organic amendments, but we caution to not use highly available (soluble) liquid nutrients in large volumes – this may cause a nutrient lockout. Read more below about plant teas.

Can I start my seedlings in Kryptonite? Many growers have great success in simply dropping seeds into Kryptonite and having germination take place in 3 to 7d. We recommend a 12h soak in water, compost tea, or a seaweed extract and then placing the seed at a depth double its thickness and then covering it with more soil or sand. Other growers like to mix a little peat or coco coir with Kryptonite. If you are planting your clones (i.e., cuttings) into Kryptonite, it’s important to remember that you only want 1.5 to 2.5 inches of nice white root growth emerging from the plug. Clones with excessive roots do not transition into a living soil and the roots tend not to occupy the entire soil surface and produce fewer secondary roots and root hairs.

Can I use Kryptonite with auto flowers? Auto flowers have come a long way and the thought that they require poor soil to initiate flowering is not necessarily the case with some new strains. Many growers will mix some extra peat and/or coco coir to Kryptonite just to decrease the nutrient density.

Can I use plant teas? Aerobic compost teas, microbial teas, fermented plant extracts, sprouted seed teas, Lactobacillus – dominant teas and so on are a real testament to the amount of traditional knowledge (and creativity) within the cannabis subculture. As we learn more about all the medicinal compounds within cannabis, more designer teas will be created to enhance a particular chemical within the plant. Kryptonite is chock full of nutrients and microbes (great worm castings) and so does not require anything but water. However, growers have their own “special” recipes and will experiment, we just caution to keep the nutrients low so as not to cause a nutrient lockout.

What size pots should I use? The size of the pot is more of a reflection of how long will the life cycle of the cannabis plant be. More on this below, but typically a cannabis plant may have 4 weeks in the vegetative period and 8 weeks in the flowering period. Highly dependent on lighting, but most cannabis strains that have been “topped” twice during the vegetative period will grow to about 3 to 4 feet in height. This plant will grow well in a 5-gallon pot. Conversely, if you choose to grow outdoors and your vegetative period is 4 months and your flowering period is 2 months, you may be wise to use a 30-gallon pot.

Is it best to water from the top or bottom tray? Most plants prefer to “drink” water from the bottom. Sub-irrigation allows plants to choose when and how much water they want to consume. Top irrigation, especially using emitters can create paths of least resistance and water will flow down to the bottom. The challenge with this in living soil is that the roots have not developed fully to occupy the entire soil area. We recommend that when you pot-up (Read more below on potting-up) for the last time that you top-water around the circumference of the pot to help encourage roots to grow towards the water. Oftentimes, growers will flip to bottom watering the same time they “flip” to flower from being in vegetative (i.e., going from a long-day photoperiod of 18h to a short-day photoperiod of 12h).

Can I add nutrients to the soil? That’s a loaded question! When you take a look at the ingredients on the Kryptonite package, there’s everything but the kitchen sink. However, as I’ve mentioned above, growers are creative and they may have a “special” ingredient that is a must-have. We don’t recommend the initial introduction of any new microbes (unless you are doing a root dip of mycorrhizal inoculant) and we don’t recommend the addition of any nutrients that will greatly affect the balance of macronutrients (N, P, K, Ca, Mg, and Na – Nitrogen, Phosphorus, Potassium, Calcium, Magnesium, and Sodium)

Do I need to rinse or clean the root system before potting up? Never. The area immediately around the root system, the rhizosphere, is like the microflora of our stomach. Washing your roots will not only reduce nutrient availability it will impact plant health.

How many times should I pot up? Most indoor growers will pot up twice from a root plug. So, a rooted clone will often be placed in a one-gallon (3.8L) pot and depending on the size of the clone it may also be topped. Approximately two weeks later (highly dependent on your growing environment) you may begin to see several roots at the bottom of your pot and should consider potting up to its final size pot for the next 8 to 9 weeks, typically a five-gallon (19L) pot. When growing outdoors, we often see growers potting up one more time (if remaining in the vegetative period for at least another month) from the five-gallon to its final container size (e.g., 30-gallon). Remember auto flowers do not like to be potted up.

Do I need to add anything to the bottom of the pots when before adding Kryptonite? If you are growing in a container and want to limit root growth from beyond the confines of the container, you may choose to place a copper-lined fabric root guard at the bottom of the pot, then place about an inch or so of medium grade perlite (please note that expanded clay pellets do not work as well as perlite in creating capillary action). Then just add your Kryptonite to your pot.



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