The Winter Grow Room

We all miss the sunshine right now, but it is easier to grow successful indoor Cannabis crops in the winter rather than during the summer.

As much as we all enjoy having a suntan and wearing shorts and t-shirts for a few months, there are a few downsides to summertime. The main downside is that indoor growing in the summer is often a bit of a nightmare. When the weather gets hot, so do our precious plants. That carefully set up grow room that sits happily at 82.4º F for most of the year and produces plenty of bud time after time suddenly turns into a sauna. Yield seriously drops and any weed that you do manage to harvest is sometimes seriously low in quality.

So, as the weather starts to change and the clouds roll in, we outwardly pretend to our friends that we are upset, when really, we are celebrating on the inside! Finally, we can get a decent crop going again.

A long, hot summer can do funny things to a grower's memory and leave them badly prepared for the cold snap. If you did not prepare your grow room for the wintertime this year, make a plan to do so for next year; if this is only your first or second indoor crop, you might have already noticed a huge difference in winter- versus summertime grow rooms. When the days get shorter, try to think back a few months and make sure that you have prepped your grow room for a chilly winter.

Firstly, it is important to actually monitor and record the maximum and minimum temperatures that occur in your room. Invest in a min./max. thermo-hygrometer; the easy-to-read digital versions can be bought for around ten bucks.

Monitor your nighttime temperatures, as these can really drop when the cold weather hits. Remember that a big difference in day and night temperatures can cause your plants to stretch, so try to keep the 'lights-off' temperature within 41 and 42.8º F of the 'lights-on' temp.

In a smaller grow room, this can be achieved fairly cheaply by investing in an oil-powered radiator and a fan speed controller. The radiator will warm up the room and the speed controller can be used to reduce the fan speed, so that all that nice warm air is not immediately extracted out of the room. You can buy a manual controller and just turn it down at night or, even better, get a temperature controller. These enable you to set your minimum and maximum room temperatures and will adjust the fan speed accordingly in order to maintain it.

For a larger room, you could heat the room from which you pull air-in, so that the air fed into the grow room is already warm. Or - if the grow is big enough to warrant it - install a boiler and a heating system.

The source from which you are ducting your air-in is very important, as cold air hitting the plant will cause the stomata (the pores on the leaves) to close; when this happens, growth will stop. Therefore, where you may have been ducting air into the grow room from outside of the house during the warmer summer months, you may wish to duct it in from a warm room in the house during the winter.

If you have no choice and must duct air-in from outside, just increase the length of ducting you use and loop it around a few times inside of a warm room. This will help to heat up the air.

If you are growing in the garage or basement, do not put pots directly onto the concrete floor. Concrete is not a great conductor of heat and it will remain cold throughout the day. Cool roots grow slowly, so put the pots onto Styrofoam or a wooden pallet to raise them off of the ground - this will also help air to circulate around the base of your plants.

If you are using a recirculating hydro system to grow your plants, then you need a submersible water heater in the reservoir to maintain temperature - the kind that you use to heat a fish tank. Set the thermostat to around 68º F and the roots will stay healthy.

Flood-and-drain systems require a shatterproof submersible heater because, when the system floods, the reservoir will empty and the heater will be exposed to air. Some of the better-quality submersible heaters on the market will switch themselves off when removed from the water and automatically turn back on when submerged - clever stuff!

It is also worth remembering that, as the temperature drops outside, your indoor grow can become more susceptible to being discovered. Think about where your ducting exits the building - in very cold weather the warm air being extracted out of your room can become visible as steam. If possible, it may be a better idea to duct it into another internal room for the winter months and avoid detection. Ideally, you should duct it into the chimney.

If you are growing in a loft during the winter, then you must ensure that the loft space has been properly insulated. When the snow comes, you really do not want for yours to be the only house on the street where it does not settle! Use a heavy-duty insulation material, such as King Span, and avoid venting warm air into the loft cavity.

It might be helpful to re-read this article when you are about to start your Christmas crop. Provided that you begin such preparations no later than the end of October, then there will still be time to get your winter grow on.

Check out the latest auto-flowering seeds from your favorite seed bank. Almost all of the major companies supply auto- versions of their best-selling strains. Yes, in most cases, the yield will be lower than from regular seeds. However, some of the faster varieties can be cultivated from seed to harvest in sixty to seventy days. You may be harvesting on Christmas Eve, but at least you will have some smoke to hit after Christmas dinner!

Happy growing!