To determine what size dehumidifier your room will need to do some basic calculations. First, how much water are you giving to your plants each day? For example, if your garden has 20 plants and you are watering with 1 gallon per plant per day you will have 20 gallons of moisture you will need to remove from your room. Since dehumidifiers are rated in pints you need to multiply the number of gallons you give to your plants each day by a factor of 8 to convert to pints, which for this example is 160 pints of moisture you will be needing to remove. If you are growing in soil and you only water every other day you will need to divide the total pints by 2 to get the average per day.
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