1. Test the pH level of the water (tap is acceptable) to ensure it's in the appropriate range for cannabis plants (between 6.0 and 6.8 for soil grown).
2. Water the plants at the time you would normally feed them without giving them any nutrients or supplements. Don't water your plants more than usual to prevent deficiencies.
3. Repeat 15 minutes later.
4. To make sure the flush was successful, use a TDS reader to measure the total dissolved solids and find out how pure the water runoff is.
It's ideal that the water draining out of the pots is as close as possible to the TDS (total dissolved solids) reading of the neutral water you're flushing with.
5. Keep an eye out for signs of too much yellowing. The pre-harvest flush may cause a plant to lose its color quickly. It's normal to see some yellowing, but it's critical to harvest before the leaves on the buds have yellowed.
Once all the leaves have turned yellow your plant is at the end of maturity and buds will start to deteriorate.
6. After flushing, your plants will be a lot lighter in color and are ready to be harvested.
Flushing cannabis is used to remove buildup from the roots and soil of a plant not. It's been recommended to flush at the beginning or the end of a day when plants can be misted (this lowers their transpiration so that they do not over hydrate).
Generally, flushing cannabis normally takes place two weeks before it is harvested. If the plant has an 8-week flowering period, flushing should start 6-weeks after the beginning of the flowering stage when trichomes begin to form a cloudy white color.
Flushing cannabis removes leftover nutrient buildup from the roots and soil of your plants giving them a fresh start. Flushing effectively allows your plants to absorb any nutrients that are still in the soil.
Flushing cannabis too early and too often will restrict nutrients and restrain the plants from growing and flowering. Flushing too early can also result in yellowing or discolored leaves.
1. Pre-harvest flush
2. Sudden change in the nutrient cycle
3. Nutrient Lockout
1. Pre-harvest flush - Flushing is used during this stage to improve the quality and smoothness of cannabis. A flush during pre-harvest will force plants to use up the nutrients stored within themselves while preventing harshness and removing excess chlorophyll.
If the nutrient reserves are not used or broken down they will negatively affect the quality of cannabis buds. This should be done between a week and 10 days before harvest and repeated three days later.
2. Changes in the nutrient cycle - Cannabis has different nutrient requirements depending on what growth stage it's in. Cleansing cannabis of old nutrients is a good way to reset soil while a plant is transitioning into a new stage of growth.
Think of this as a preventative flush. It's not required, but by the time a plant reaches the flowering stage, it has sucked all the nutrients from the soil and could benefit from a fresh start.
3. Nutrient Lockout - Growers that understand how to balance nutrients individually don't have to worry about flushing as much as those who rely on pre-balanced nutes.
Using pre-balanced nutrients may offer immediate results, however, after the first few doses, your plant is likely getting too much of one nutrient and not enough of the others creating a deficiency. A deficiency in plants is not always due to a lack of nutrients but can be because a plant has too much of a nutrient causing its system to become unbalanced.
By overfeeding plant's nutrients, they will absorb what is needed while the access sits in the soil. This leads to a build-up of unnecessary nutrients which is known as Nutrient Lockout.
Generally, when dealing with a serious nute imbalance, the cure is to flush the plants and add a fresh, well-balanced, mild dose of nutrients. It's important to pay attention to the details; don't just flush cannabis because of minimal changes.
If you notice a drastic change in your plants but there are no other issues (heat, root rot, etc.), flushing may be a good idea to remove excess build-up and help restore the soils pH balance.
Use our sizing calculator to help you determine which unit is best for your room and how many units you need to acheive proper air circulation.
|Room Measurements (feet)|
To clean Square Feet, you will need:
A CleanLeaf media air cleaner is considered an "ambient air cleaning system" designed to run ambient shop air through a series of high efficiency filters and/or carbon depending on the application. When sized for 8-10 air changes per hour, you will create a constant reduction in the amount of airborne particulate in the room between 70-90%. We always recommend capturing the particulate at the source when possible but understand source capture is not always an option. Blue Ox air cleaners are often used as a secondary filtration system to source capture or when source capture is not applicable.
1. First, we determined the air changes per hour requirement from the following:
2. Second, we determined the required CFM for your application:
Sq Footage = Length x Width x Height (We use 12' by default)
Total Required CFM = Sq Feet x 8 Air Changes per hour / 60
3. Determine the total number of units required:
Total Units = Total Required CFM / Unit CF Rating
For Example: 12,000 Required CFM would require (4) 3,000 CFM units