This is the address I see I went to last night:
How do I get to the URL where the calculator is? I can't find it today.
www.zoho.com -> Zoho Sheet -> Public Sheets
Then put "dewpoint" in the search box.
The link I put in your original post works, too.
If you have MS Excel, the easiest thing is to export/download the calculator. The first time I tried, the IE7 popup blocker stopped the download, but once I allowed the download, I was able to download the Zoho version in its original form. If using Firefox, the steps are:
1) Go to the calculator using the steps above2) Click Export -> MS Excel Workbook xls3) Save to disk -> OK
You can close the next window, the file is already saved, probably on your desktop; if you click open on the next window, it will open your desktop version.
And it is yours to keep for all time!
It's very small and on the bottom of the page. Very easy to miss.
OK. I entered the temp and RH and hit enter. So far nothing happened expect the little black square moved down one space.
I do not have MS-Excel or MSWork-books. When I tried to export it this is what I got:
Error OccurredUnable to Export the DocumentHow can I get it to work right there on the page?
Could somebody do me a favor? Go to this link, see if the spreadsheet opens, then change the temp and/or the relative humidity and see if the VPD changes accordingly?
Everytime I go there it changes the numbers for me as it should. But GHer can't get the numbers to change for her. I can't tell if it a problem on GHer's end or a problem with the site generally.
Please don't change any of the formulas, BTW.
Here is a link that might be useful: VPD calculator
Stressbaby I did it last night using the link and it worked just fine. You have to wait a little bit for the page to set itself and then enter your numbers and it calculates for you. Thanks this has been very educational for us newbies. I have it downloaded on my computer. Thanks Barb
The VDP, in bright blue says 0.40 and the DT, in bright blue, says 54.
So what does that mean and how do I make use of this information? ????
Gher, My understanding is that we need to keep the VDP number between 0.5 kPa to 0.95 kPa. if we keep between these numbers we will have happy plants. No mold Yipee. I hope this helps. Barb
So is the calculator working for you?
The VPD is described in detail in the post I pasted and in the links at the bottom of that post.
VPD of 0.4 kPa is not ideal. Too humid. Somewhere in the 0.5 to 1.0 range is better. Much more than 1.0 is too dry.
BTW, thanks for trying the calculator and reporting, rosepedal.
How are you getting rid of excess humidity? If I vent my GH or leave the door cracked the temp will drop and the heaters will be running full out.
OK, I'll look for it. It should be in the other thread. I didn't understand it the other day but will read it again and see if I can figure out what these numbers mean.
Gher,My gh will not be running until next month. Did you put your extra fan in there? It sounds to me, that when you added all of the extra plants from the hfgh, you crowed the rion and need to circulate more fresh air amongst the plants. They may be too crowded and need elbow room to breathe. Just a thought....... Barb
That is for sure part of the problem. There was more air circulation before the other plants were added. I plan to remove more plants tomorrow. Some that are borderline and just suffering old age such as a large spindly basil and a coleus. There are too many plants in there and because of the cold, not enough fresh air either. It's a combination of things. But even stuffed to the rafters last winter the HFGH didn't have a humidity problem.
I tried to fit the fan I just dug out of storage out there somewhere. There is simply no space for it. I can't have it blowing directly on the plants only a few inches away. Maybe tomorrow I can come up with something. Maybe I can squeeze more plants into the sunroom so there's a place for the fan out there.... eee gads,... this is insanity. =:-O
I don't know how I can keep it between those values and not either chill the plants to death or go broke heating the great outdoors. I'm going to try and fit more plants in the sunroom and try and get the fan in there somewhere. If we'd only get some sunny days. All this damp dreary overcast cloudy weather isn't helping. The vents stay closed and the air, even though 3 fans are moving it, stays stale and damp.
I am new to greenhouses so please forgive me if I am stating something off the wall.
During the winter, is it perhaps better to keep your plants a bit on the dry side? Would this have eliminated Greenhousers problems?
Most of us are addicted...thus the greenhoses...so we will inevitably fill our greenhouses to its maximum capacity or more...which appears to be one issue greenhouser is experiencing (not enough air circulation.)
However, what is the downside for leaving the plants a bit drier during the winter months when the weather is too cold to open windows, vents etc.? I'm assuming this would also decrease the humidity not?
As I said, I'm not an expert, just trying to learn so that I don't create an environment in my newly built greenhouse which would render all my plants to perish.
I do believe that if you can get enough air circulation it may prevent some of your problems. Can you mount the fans on chains in the upper corners of your greenhouse? I would suggest mounting them on L' brackets but I'm not certain that is possible in your greenhouse???
I do work part-time (in addition to my full-time job) at a small, family owned nursery during the summer months and air circulation is vital to keep all the plants alive that we grow. But I've never had to work with over wintering them. I'm thinking there is an entirely different list of problems that can be encountered. ha ha
There are fans hanging in the GH that run 24/7. They're just above the plants. One faces east and the other west. I added another smaller fan to blow across the floor area. Today a added an oscillating fan blowing from side to side, sweeping the mid section under the benches. Since it's sunny and 64F today I also put a temporary fan just outside the doorway to blow completely fresh air in down the isle. That should help push stale humid air out the vents. So there will now be 4 fans running covering every section of the GH and the Outside temp' fan when it's above 60F.
I am bumping this thread. Stressbaby and others have great info here to get us through winter regarding humidity. Barb
I tested the zoho.com link and the VPD-dew point calculator is still there. The links and export instructions look like they are unchanged.