Quote:
Originally Posted by GpsFrontier
Hello jhinkle,
I have a few questions:
1. How often do you change your nutrient solution?
2. How much nutrient does JRPeters recommend using for a full strength nutrient? I believe they go by weight (something like 11.4 oz) per 100 gallons. They do for the herb formula anyway.
3. How much are you using?
4. What is the humidity?
5. Do the white spots feel powdery?
6. Can you smear the white spots?
7. Do you notice any insects around the plants? Especially like tiny white fly's, spider mites, or aphids etc..
P.S.
I would pluck off the leaves with the white spots. Also I would put them in an air tight bag or burn them to get rid of them. |
Funny you ask question #1 -- about changing out the nutrient solution. I read a paper from cornell univ:
http://www.greenhouse.cornell.edu/cr...ic-recipes.pdf
I spoke at length to Dr. Cari Peters on that subject. Cari stated that changing nutrient solutions was necessary when the fertilizer being used was not properly designed for hydroponics and overtime the nutrient ratios would change as some
nutrients were consumed faster than others.
I grow lettuce and tomatoes and asked specifically about those two. Cari stated that Jack's 5-12-26 + 15-0-0 calcium nitrate did not require changing except at the end of the growing cycle. Cari stated that the nutrients in the hydroponic mix was all soluble and mixed in the proper ratios to make intermediate changing not required. This is my first try at tomatoes so I will see how well things work out.
Question #2&3 -- The Cornell paper -- 360 grams of each are for 100 gallons. Jack's blog states 368 grams.
I use 3.68 g per gallon --- I uses a scale with .01g resolution.
Question #4 -- I'm right on the ocean - 85 to 90% is what weatherbug states.
Questions 5&6 -- I just went out and cut every stem that had white marks on them. I brought one inside and looked at it under a microscope. It looks like patches of small spider webs. You can smear the white spots - as is you are collapsing the web and smearing the strands together.
Question #7. I have looked and found no insects.
Do you have an idea/guess as to what the white spots are? If insect -- how to get rid of them?
I grew tomatoes for several years in earthboxes down here and had no insect problems. Two years ago - and for a two year period -- I had an invasion of what I call tomato worms. I have not seen any sign of them as of today.
I started late (I wanted to grow from seed) so I purchased these 4 plants from Home Depot. I usually don't like to buy plants from them as I have found they come with insects and issues. Maybe my white spots were there all the time and I did not notice them with the plants only being 4 inches tall.
I appreciate your comments and would love to hear your comments based on my answers.
Thanks