First time attic grow journal.

First post, first grow

Last week I decided to some home grow at my attic. Picked up a 600W HPS, carbon filer, relay box, fans and some other stuff. I had my concerns about the heat this 600W HPS would produce but I decided to set it up. Unfortunately the temperature was rising and stopped at 36 C/ 97 F. I could not get it down especially because it is summer and the outside temperature was 25 C/77 F. The only thing I could think of to take 4 Cool White FL of 63W each and hook them up. Four warm white FL will be used for flowering. The HPS will be used in the winter (Grow journal number 2?).

The equipment is installed. The carbon filter will be installed later because I will need the fan to get as much warm air out of the attic as possible. I used reflected radiator foil to keep the light as much as possible on the plants.

20KG of organic soil in the pots, 0.5 litres water each and let it set 24 hours. Now it was time to turn on the lights and get my four PP clones into the soil. They will be on 18/6 for about 10 to 14 days if everything goes well.

The first week I will give approximately 0.2 litres a day without any fertilizer. After a week I will start with a biological fertilizer (7-30-20, low concentration).

Hopefully I have time to update this journal once a week. Any comments, questions or ... are welcome.

Relay box.

Setup.

PP1 still a bit stressed.

PP1 close up

The last one for today.

I thought the marijuana plant could withstand 100 plus degrees. If the grow is in the attic why not use the HPS, does the heat spread to the rest of the house?

Originally posted by woody
You're from Holland? If so, I may have some usefull PP advice for you, especially regarding ferts.
Peace.

Hi Woody,

Yes, I am (Utrecht). Any tips are welcome.

Originally posted by Pothead Pete
I thought the marijuana plant could withstand 100 plus degrees. If the grow is in the attic why not use the HPS, does the heat spread to the rest of the house?

Unfortunately it is a very small attic (1.5 x 2 x 1.5 meters). I turned off the HPS after an hour. At that time it was over 97F. Maybe when the young ones are a couple weeks I could give the HPS another try.

Use a small oscillating fan. It should help to keep your temp. to a tolerable level for your plants. Unless they all start to get dry why not use your HPS lights. The pot plant can be quite hardy under the right circumstances. PEACE!!!!!!!!!!!!!!!!!!!!!!!!

Yeah I agree with THC. A small fan might work but an A/C is the wisest option for your attic grow. Can you afford one?

The heat problem has been solved. I added a second intake with a fan. The temperature with lights on is 26 C / 79 F (max) and lights off about 23 C / 73 F.

Next week will be a test with outside temperatures of > 27 C. May be I need to hook-up my small A/C.

The clones are now 9 days on 18/6, growing about 1 cm a day and are about 17 cm tall. I had to adjust the height of the FL’s to avoid heat burn. I’m probably the first one to get a heat burn from FL’s Over the last seven days I lowered the PH in the water to 6.3. No ferts yet.

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How tall are your plants?When is projected harvest date?? HE HE HE !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

Hi Pothead Pete,

The girls are about 17 cm/6.7 inches tall. Haverst time in about 9 weeks?

Any more cool pics?

15 th day veg.

I’m a bit surprised that they survived all the heat stress of the last two weeks. They are starting to get real bushy. Some purple coloring but nothing to be worried about I think.

PH is now down to 5.9. The height of the plants varies from 17/20 cm (5.5/8 inches). I will be switching to 12/12 at the end of this week. The growing space is limited so I have to force the flowering process somewhat early.

As from yesterday I started to use some ferts. B’Cuzz grow and B’Cuzz booster. Just 1/3 of the recommended amount on the bottles.

Here are some new pics that I took yesterday evening. Didn’t have time to take some good pictures, so they are a little dark and out of focus. Sorry about that. I will take some good shots the next time.

PP2