Browning tips on Sans
This may be a bit long but I want to make sure and give you all the details.
This past summer I purchased four beautiful amost 3ft tall Sansevieria plants. Two are the deep green with lighter green stripes and the other two with deep green and lighter green stripes with a lime/yellow variegation on the outer edge. They were doing great until about a month ago. It has gotten very cold recently, have forced air heat, and I keep the thermostat at 69 degrees. Two of the Sans, I have in our den and are doing great from what I can tell. That room is smaller (8 X 10) and a bit warmer, with no drafts or doors being opened and closed. The other two Sansevieria (with the variegation) are in the front living room, (16 X 20) They have suddenly started to turn a yellowish brown and look like they are drying and wrinkling/shriveling on some of the tips in the center of the plant. It almost looks as though they are drying out at the tips and working it's way down. The bottom of the plants, look very healthy. I have clipped off the bad tips and it seems to continue down the leaf. I was keeping them on the floor next to our fireplace (about a foot away on each side, so they wouldn't get heat damage) We only have used it twice this winter and they were not receiving the hot heat of the fireplace. However, I realized that they were in front of return vents. I was worried they may have gotten to drafty from when the front door was opened (which is across the room diagonally from the plants) when the heat kicks on, It would suck the cool air past the Sans and into the returns. I recently put them up on plant stands in the same area so they are above the return vents by about 2 ft. and warmer. The tips of the leaves are now about 4 feet off the floor. I'm not sure if this was their problem but I didn't want to lose them so this is where they are now. I just recently read that they should not be watered from above, near the center of the plant, only around the sides and not to wet the leaves or they can rot. Unfortunately, I have done this (before I read that you shouldn't). But it hasn't seemed to bother them all these months. I also read they should be watered very sparingly in the winter. I am worried that they are drying up, but I am afraid to water them too much. I have been watering them all about every 4 weeks by wetting the soil and letting it run through, then letting them drain completely so there is no sitting water. Although the past month or two I have not been doing this for fear of over watering in the winter, so I have been adding only about a half cup of water around all of the plants about every 2 weeks The two in our other room are doing fine, and I keep the soil the same (to the touch) in all of them. Pretty dry, feeling ever so slight dampness if you put your finger about 2 inches in the soil. The only thing different I have done was change the pots on the ones that have damage. I put them in a nicer stoneware pots that were almost the same size, just a bit wider at the top half than the plastic pots they were in. I filled in the gap with miracle grow cactus mix but they are basically in the same soil. They have been in those pots for a while now, well before the damage started. I love them and do not want to lose them. Do you think it's the temperature in the room, chilling the stoneware pots & the position they were in before I put them up on stands or possibly not enough water? I will try to post pics as soon as I can.. Thanks :)