Greenhouse nutrients tips??

[MendozaFarms]

 I just ordered 10 seeds from Barneys seed bank. And I really want to get it right this time. Wanting to learn what the best greenhouse strains with the right vitamins and measurements. Thank you. Very glad I made this account? help a  California girl out ☺

[Cannabissapean]

Hi Mendoza,

Your question is really a thousand questions all rolled-up into one, so I'll try to give you some good answers.

 

If you want to grow in soil, look online or in YouTube for recipes for "supersoil for cannabis".  Get those ingredients, mix them up and let it sit 2 or 3 weeks (or longer) before planting into it.  That soil is for the pots.  However, the soil for the seedling in its first few days must be more gentle.  For the seedling cup, I use seedling soil (found in every home improvement store or garden center).  I allow the seedling to develop its initial roots in seedling soil, and only when it finally shows roots coming out the holes at the bottom of the cup, do I make the first transplant into the final pot with the supersoil.

 

If you want to do hydroponics, first watch on YouTube "Mr Green, I grow Chronic".  He shows you how to build your own home-style hydroponics set-up.  It works.  For the Rockwool cubes, they are available ready-to-use from Grodan.  Or if you wish to make your own, you can purchase a massive rockwool cube at a home improvement store (or industrial insulation supply), cut them down to 6 x 6 x 6 inch cubes (bore-out a ~1,5 inch hole in the top for the initial cube), wrap each using duct tape, and you basically have the same thing as a Grodan cube; just be sure to soak them in acidic water (~3,0 pH) for a day or two before use.  Industrial rockwool has a very strong tendancy to push the pH upwards for many days in hydroponics if it is not first thoroughly soaked in an acid bath for a day or two.

 

My favorite method of germination for either of the above grow-methods is the "paper-towel germination method".  After the root has emerged and stretched about 10 to 20 mm, that's when I transfer the seedling into the seedling-soil for a soil-grow or into the initial rockwool cube (1,5 x1,5 x 1,5 inch) for hydroponics.

 

Vitamins and measurements?  We use the terms nutrients, amendments and corrections.

Again, this depends on your method of growing. 

 

But before I explain nutrients and amendments, I want to explain pH and its correction.

 

Measurements and corrections:  The most important aspect of Cannabis culture chemistry has to do with pH.  The plant's roots work most efficiently when the surrounding medium (soil or hydro-solution) is within a particular pH range.  Certain minerals are absorbed best inside those ranges.  When the pH is outside that range (too acid or too alkaline), then the root can no longer make nutrient and waste exchange with the soil.  We call that "nutrient lock-out" or simply "lock-out".  It is highly recommended that even a beginner cannabis-grower should purchase a good pH-meter.  pH color strips are simply not precise enough.  Get a good pH-meter.  Your results will most likely be disappointing if you don't monitor and control pH.

 

In general, Cannabis enjoys feeding water around pH 6,2 when in soil.   For hydroponics, Cannabis enjoys reservoir water around pH 5,8. 

 

After mixing the nutrients into the feeding water, stir and then let the solution sit for about 15 minutes, then measure the pH.  Depending on the water you are using, the pH is normally too high or too low (usually too high).  Using drops of a pH-Down Solution (or pH-Up), adjust the pH.  Try not to overshoot when adjusting pH because every reversal adjustment starts to create excessive salts that can become toxic to the plant.  Most any hydroponics supplier (online or brick-n-mortar) has reliable pH-adjustment products. 

 

For pH-Down, there are basically two types: Nitric-Acid (~35%) for use during Vegg when the plant needs Nitrogen-based compounds, and Phosphoric-Acid for use during flowering when the plant prefers Phosphorus-based compounds.  pH-Up-Solution is also available, but because my feeding water always tends upward, I use pH-Up solutions almost never.

 

These numbers 5,8 and 6,2 are general targets for adjusting the pH of feeding solutions.  The actual results at the roots will vary.  The pH of most hydroponics reservoirs tends to rise over time, and may require tweaking every couple days.  And soils will also cause pH to vary within the soil as a result of various microbial activity within the soil.  These pH swings are normal and no cause for alarm.  In fact, mild swings are actually OK, because some minerals are exchanged better during raised pH periods while other minerals are exchanged better during lowered pH periods.  There are "charts explaining mineral exchange for cannabis" that can be found online. 

 

If you do not wish to procure the formal pH-Down/Up products, you can use substitutes although these substitutes are not as pure nor do they hold the pH as stable as the formal products.  For pH-Up, you can use baking soda or baking powder.  For pH-Down, you can use lemon juice concentrate or Oak-Extract-Acid (available at aquarium supply stores, normally used to lower the pH of fish aquariums).  No matter which of these products you use, be careful with your eyes and skin; these are strong acids and alkalines.

 

When growing in soil, especially when dealing with a new soil mixture with yet unknown properties, it is also a good idea to measure the pH of the run-off water coming out the bottom of the pot after each watering.  This will give you some idea of the pH-environment within the soil so that you can ajdust your target pH somewhat (~+/- 0,5 pH max).

 

 

For soil, your nutrients are basically found in the soil mixture that you prepare.  Amendments are the various things that are added to the soil in order to optimize the availability of certain minerals and nutrients.  In your area, you should be very happy with the soils and amendments and nutrients available especially from Fox Farms and Happy Frog.  There are many more companies with similar products, but I know that these are trusted and well known.  Other good names if you can get them are Plagron, Bio-Bizz, HESI, Canna, and GreenHouse Powderfeeding.  Be aware that the use of pre-fertilized soils like Miracle Grow may result in undesired affects because the added fertilizers are not optimized for cannabis and the nutrients are sometimes "time-released" resulting in wild nutrient swings at the wrong times for cannabis.  When mixing nutrients into water, it is recommended to mix at only HALF the manufacturers recommended dosage for the first couple feedings.  After that, you may increase the dosage at your own risk, but normally never more than the recommended dosage.  Remember, the soil also has nutrients in it as well.  If you are like me, once I see that the plant is happy and healthy after 2 or 3 nutrient feedings, I stop adding nutrients.  From then on, I water with just pure rainwater until it is time to change the feedings to foster flowering.

 

For hydroponics, in your area, you should be able to find liquid nutrients from General Hydroponics.  The products from General Hydroponics are very similar to those from Advanced Hydroponics of Holland.  Other good names if you can get them are Bio-Bizz, HESI, Canna, and GreenHouse Powderfeeding.  Be aware that these companies make products for soil and products for hydroponics.  Products for soil are normally not suited for use in hydroponics because they may clog your pumps or drippers.  The water used in hydroponics should be very clean to avoid problems with pumps, hoses and drippers.  Again, when mixing nutrients into water for hydroponics, it is recommended to mix at only HALF the manufacturers recommended dosage for the first couple feedings while the seedling is so small.  After that, you should increase the dosage to the recommended dosage.  Remember, in hydroponics, there is no soil with nutrients; YOU are providing the plant ALL of its nutrients in the reservoir fluids.  Reservoirs should be thrown out and replenished every week or two, otherwise the salt build-up can become toxic for the plant.  If you are going to go hydroponic, there is another meter that you should definitely get.  An EC-meter.  The EC-meter measures the electrical conductivity of the solution.  The elecrtical conductivity is the means of determining the strength of the solution (similar to the concept of parts-per-million).  Monitoring EC as well as pH is important in hydroponics to ensure optimum feeding, that you are not over-fertilizing nor under-feeding the plants.  This is especially important when using some products like Powderfeeding, where the dosage charts are based on EC and pH together.  I recommend the EC-meter from BlueLabs called the Truncheon.

 

Regardless whether in soil or in hydro, at some point in flowering (I recommend 2 or 3 weeks before harvest), you should stop giving the plant any further nutrients, and instead feed just water.  For soil perform a flush (water with 3-times the volume of the pot, allow it to drain away, and then allow it to dry out very well before resuming watering), and thereafter, just water.  This is to rid the soil of all excessive nutrients and salt buildup so that the plant can begin to do the same.  The plant needs to rid itself of the excessive nutrients and salts within its tissues during its last remaining living days.  If not, the resulting product will be a harsh and bad-tasting smoke; it will be difficult to light or to keep burning.  Instead of the optimum white ash, it's ash will be black because it is loaded with chemicals and salts.  A properly flushed and chemically neutral plant material will be a sweeter smoke and better tasting.  Don't forget to plan ahead for the flushing.

 

Water:  Some city water has too much chlorine and fluorine in it which is less than optimum for the microbes and could be detrimental to the plant.  Or sometimes too much dissolved calcium or dissolved iron.  These dissolved minerals present an already high EC, that can cause faulty interpretations of the strength of the solution or may produce mineral-toxicities in the plant.  These conditions are relatively rare, but if you seem to be having problems keeping plants healthy no matter what you change in other areas, then consider that your water may not be in order.  I like to use rainwater, but persons living in areas with high air-pollution may desire to avoid using their rainwater (unless you don't mind smoking re-burned SMOG).  Distilled water can be used, but it is relative expensive and is virtually dead.  Some people use RO-water (reverse osmosis) filtered water for their solutions or watering.

 

OK, I hope that helps...

 

Start a grow journal when you can.  Show us what products you will be using and let's see some beans start cracking soon.

 

Have a good grow.

 

Have fun...