I'm curious if my plants are experiencing stunted growth. There about 8 days old and are only on their second set of fan leaves as you can see in the picture. The tallest is around 4''. Early on they experienced a bit of heat stress when I had them around a foot below my 400w HPS light. The leaves lost some of their color and turned a bit yellow. Also, I noticed my ph level seems too high...a little above 7.0. I'm using SuperSoil mix with perlite and vermiculite in equal parts. My questions are one, are the plants growing at a normal rate, and two, why are my leaves yellowing a bit? Is it from the pH being too high? How far away should I have my light (400w HPS Hortilux bulb)? Thanx for the help.
Well, i don't recommend starting under an HPS at all, you should primarily do the seedling stage under fluro's than switch to HPS. Also what is your NPK of your super soil mix? Well from a rough diagnose, its the soil, i'm not sure whether you put nutes in their already or whether your NPK is incorrect for the type of plant your trying to grow. btw, why didn't you fill the soil to the top? you plant on transplanting those?
Actually I did fill the pots to the top with soil, but after watering them, they have compressed a bit. I do plan on transplanting them to bigger pots in a few weeks. The only soil that I could find locally was the Super Soil (.14-.09-.02 NPK). So, are the plants not growing as fast as they should? I'm growing in my closet which is 4'x5', how far away should I have the 400w Hortilux HPS from the tops of my plants? Anyone?
a 400w HPS can go as close as 18" from the plants if its a lot higher then move it down to about 20-21" at first and then slowly wove it down till its about 18" away a good trick is to have a peice of string 18" long hanging from the end of your reflector
...well in the beginning I had them only about 13" from the plant which is when the yellowing started. I moved the light up to about 19" but the leaves still look yellowish and the growth isn't as good as I think it should be. I was thinking the ph level is too high because it reads right about 7.3 or so. I plan on using ph adjusted water tomorrow to try to bring it down some. I used some pH down that I had. When watering to lower the pH with the adjusted water, do I water normally or do I use a lot more water than usualy??? ...and my soil isn't great since it still has trace amounts of nutes in it, but I used a light mix using 1/3 perlite and 1/3 vermiculite with it. Do you think the soil could be causing the yellowing too??
Even when they haves minimal nutes in it and is mixed lite in the soil mixture? Does anyone think the alkalinity in my soil is causing the plants to turn a bit yellow?
Even when they have minimal nutes in it and is mixed lite in the soil mixture? Does anyone think the high alkalinity in my soil is causing the plants to turn a bit yellow?
I had the same problem- here's what you have to do: start them off 3 feet away and not directly under the light when they're seedlings- then when they're 2 weeks old start moving them a little closer day by day until they're about a foot tall and then when u initiate flowering, keep them at 18 inches away-- trust me- it works- do it unless you don't want stunted plants in which they would never reach a foot tall, which is needed for flowering good buds-- btw- its not the nutes
3 feet? That seems awfully far. I moved the lights to 24" from the plants and I plan on adjusting the pH level tomorrow. Hopefully that'll work. At 8 days old, how big should the plants be now? Do these look stunted already??
When checking the pH level, do I use a soil meter and check the level of the actual soil or...should I check the pH level of the run-off water?? Also, should I leave my plants 24" from the light as they are now or should I move them closer?
I don't have a soil meter, but if it checks pH then use it. I used to check pH in run off with the strips like back in 8th grade science. I now have this little gizmo where you mix a soil sample from a couple inches deep with some powder, add water, and it'll turn colors. But if you have something that gives you a straight number answer, it's a lot simpler than trying to decide whether you have a forest green or a pea soup green.
Well...I watered today with pH adjusted water. It's been an hour or so and my soil pH is still about 7.0. That's strange. Does it take awhile for the difference to show? Also...before I watered I made sure my soil was dry an inch deep but after looking at my plants, they look a bit overwatered. Will they recover? My last question is one I asked already. How far should I keep my 400w hps from my plants?
hello matrix! I recomend putting the light 24- 36" away. Thats along way but this will ensure your light isn't to much for the babies. Your soil is keeping your ph high. You can make the nutrient mix as low as 5.5-6 ph to help. Since you just fertilized relax; it takes time for the plants to recover, sometimes a week or more! be patient. when they start growing again move your light closer inch by inch. don't over do anything slow'n'steady.....
3' is about right for sprouts but as yours are over a week old, 2' is good. If the plants have heat damage, the plants will hold off growing as it will have to grow new leaves to replace the heat damaged ones if they are too bad off. This will affect growth but MJ is actually pretty hard to kill so they will recover. you probably should look around for new soil. They are probably out now as the season is way over, but the dollar store sold bags of suprisingly black, no fertsadded, potting soil that I would definitely try in a pinch. The problem now is most stores stop stocking gardening stuff in July or so. Adjusting the pH of the water really won't do much to change the soil pH so your best bet would be to find clean soil. Sunshine mix #4 is carried by some chain stores followed by promix which is ok, ph 5.5 tho. Foxfarm is obviously the best but expensive and hard to find outside of hydro stores. I have seen new MGrow soil without ferts and have read others are using it with good results so far. If you are really stuck with the dirt you have, you might try adjusting the water pH low, pour it through the dirt and measure the runoff to try and get it to 6.5. Not sure if that will help though. Just a guess.
I appreciate all the help I've gotten so far. I'm using seeds from a seedbank (which aren't so cheap) so I'm trying to make sure not to waste them. I just purchased some Fox Farm Ocean Forest potting soil so that I can transplant my seedlings. My question is whether I should transplant them into the same size pots (6" 1.5 qts) or should I transplant them into bigger pots (3 gal) as the plants are still small?? Should I transplant now to see if that helps??
I would go a head and transplant to a larger container and remove as much of the old as possible without damaging the roots. And get that PH down, memory serves me right you should be running between 6-6.5! Your light needs to remain atleast 2' and it wouldn't hurt to have it a 3', a 400 HPS will penetrate 3' effectively.