Auto-flowering cannabis under LED

Cannabis seed in a glass of waterToday I have started a grow. An indoor autoflowering cannabis grow. I have ordered a 300w LED growing light on the Aliexpress website. I have ordered my automatic flowering cannabis seed. I am ready to start. At this moment my auto-flowering seed is floating in some water in a glass that stands on the box of my PC.  Nice warm temperature in 2 days it’s seed shell  will crack and I will put it into a small pot with good potting soil.

Potting soil for weed

What is the best potting soil for auto-flowering weed?

I have learned that good potting soil for roses or other flowering plants is just fine. So why make things more complicated by trying to mix your own soil? Don’t buy cheap potting soil but just take the best potting soil available for flowering plants.  I have bought a sack of soil for 12 dollars at our local garden center.

If you still want to do things the hard way, here is a cannabis potting soil recipe.


Recipe for autoflowering cannabis potting soil

Cannabis Potting Soil Recipe 1:

cannabis potting soil
recipe for weed potting soil

1 Bale sunshine mix #2 or promix (3.8 cu ft)
8 cups Bone Meal – phosphorus source
4 cups Blood Meal – nitrogen source
1 1/3 cups Epsom salts – magnesium source
3-4 cups dolmite lime -calcium source & pH buffering
1 tsp fritted trace elements
4 cups kelp meal.
9kg (25 lbs) bag pure worm castings

– Mix thoroughly, moisten, and let sit 1-2 weeks before use.

Cannabis Potting Soil Recipe 2:

40% composted soil
30% worm castings
20% perlite
10% dolomite, guanos, goodies, etc.. i’ve also heard good things about “uncle
malcolm” brand soil from peaceful valley is good….

if you’re mixing organics with chem ferts, the plant will use up what the chem
ferts feed it first, then partaking afterwards in the organic nutes. the beauty of
organics is it’s almost impossible to burn your plants, and the taste is superior to chemical grown plants.

i use pure blend 1 – 0.5 -1 for veg and fox farm big bloom 0.8 – 3.0 – 1 for
flowering. they’re expensive but the plants really like it. sometimes i’ll make a tea out of worm castings & guano



1. Making the base
The first step when making the right potting soil mix for growing weed is looking for high quality organic soil, which will act as the base. The base soil can be defined as the regular soil that will be used in the pots without any other additives. Selecting the right base soil is very critical when it comes to growing cannabis. Most beginners will fall into the trap of cutting corners when choosing the base soil. However, this is detrimental to their venture considering that cannabis grows well in aerated and permeable soil. You should look for good organic soils that tend to be more expensive because they have the right ingredients. A balanced organic soil will usually contain several ingredients, such as peat moss, bat guano, soybean, earthworm castings, soybean meal, pumice, compost, lignite, green-sand, glacial rock dust, oyster shell flour, k-mag, coco fiber, perlite and leornardite. If you find a local mix with most of these ingredients, then you should use them as your base.

2. Adding other nutrients
Considering that it might be difficult to find an organic soil with all the appropriate nutrients, you must consider supplementing it. Some of the ingredients that you need to add include steamed bone meal, organic worm castings, bloom bat guano, blood meal, rock phosphate, Epson salts, sweet lime or dolomite, azomite to provide the plant with trace elements and humic acid. Most of these ingredients are readily available and provides the right nutrients for your cannabis. One ingredient that you may find hard to get is the worm castings, but you should never fail to use them. The beauty is that you do not need a soil conditioner if you use worm castings.
weed soil mix
3. Mixing up the ingredients
It is very important to mix all the ingredients well for effective results. You can place a tarp on the patio or garage or sweep the floor and use it directly. This is usually a strenuous activity, so be careful not to pull a muscle. Some people may rent out a cement mixer to avoid the hard labor, which is fine. The method used to mix all the ingredients properly does not matter, as long as the end results are perfect. You should start by pouring a few bags of the base soil on the tarp or floor and then making a mound. Add the powdered nutrients in the center of the mound. Cover these with more base soil and continue alternating the two until everything is added. After this, turn the soil thoroughly using a shovel until it is thoroughly mixed. The end result is the perfect soil mix for growing weed.

Pots for growing weed

I don’t know if it is better but I always start with a small pot to transplant it later to a larger pot. One germinated weed seed per pot. Just save the plastic pots of the plants you buy for your garden center for later use. After cleaning them with water and chlorine you can be sure there are no traces of fungus or insects left behind and you are ready to plant your cannabis seed.

Weed Seed Germination

After two days in the glass of water the weed seed is cracked open and is the small root showing. The beginning of the germination of the autoflowering cannabis seed. Time to move the seed to the pot. Cover the weed seed under a thin layer of potting soil, don’t push the soil together. It is important the soil contains both air and saving light bulb

From this moment on the seed is in need of light.  It is a waste of energy to use the 300W LED light in this stage so I am using a 4W energy saving light bulb, as close as possible to the soil. This way it gives enough warmth and light for the first days of my cannabis sprout. Of course don’t do this with a regular 60W lamp or you will burn the weed sprout. A regular lamp produces too much heat!
Weed under fluo desk lampA flexible desk lamp is perfect to move the light close to the soil.  In the picture I have lifted up the lamp a little but in use the lamp is covering the pot completely.

The soil must be wet, not soaked. After a few days we will see the seed shell being pushed out of the soil by the growing weed root.