The temperature in your grow room is very important for the photosynthesis of your marijuana plants. For example, low temperatures reduces evaporation through the leaves. The result is that the suction force, which takes up nutrients via the roots, becomes smaller.
Yes, you can make contributions to your IRA, subject to the IRS annual contribution limits ($5,500 for the 2015 tax year, $6,500 if you're age 50 or older). But you must keep Roth IRA and traditional IRA money separate.
Source: Tax Topic 451, Individual Retirement Accounts, IRS.gov. You can contribute funds to your traditional or Roth IRA at any time during the calendar year, and you can make contributions to an IRA by the first deadline for your tax return without any extensions.