Hi citrus experts out there, I bought a container meyer lemon in July. It looks to be about 2 years old, already had 2 lemons (see pic). It was outside on my balcony in Brooklyn, NY, now it is in the window. It gets plenty of southern exposure. I noticed what I think is scale about a month ago...I picked them off, but more have returned (see pics). I bought some All Seasons horticultural spray which I plan to use but before I do..I have some repotting and timing questions: 1. I think the tree needs to be repotted...the roots fill up most of the container. However, since it is fall, should I wait until spring? Also, the tree just blossomed, would repotting ruin the chances of bearing fruit from the blossoms? 2. When should I use the spray? After I repot (if I should repot?). I don't want to stress the tree out... 3. The tree lost a lot of leaves over the summer which dropped with the petiole (stress I think)..as per the advice from other threads in this forum, I fertilized and watered with epsom salts. It was fine but now seems to be losing leaves again. They quickly turn yellow and fall off (without the petiole), not sure if this is because the pot is too small? I only water when dry, and fertilize with Osmocote Plus (15-9-12) which was the best I could find. I would greatly appreciate advice on repotting, timing issues, and scale treatment. Thanks so much!! Rachael
One more thing... I just checked out the soil closely and I found several very tiny silver millipede looking insects. They all appeared to be dead and I couldn't see any lives one but who knows what lurks below. Not sure if I should stress about this as well?!? Thanks again for any help! Much appreciated, Rachael
Hi Rachael. I dread the day I find scale on my citrus! You did well eradicating them before. Again, just pick them off, checking the tree thoroughly. They ones that are armored are the adults and are not mobile, but the young ones can lurk anywhere and move quick! I am unsure on the use of the spray - I haven't had occasion to use them before. A friend of mine uses a spray she made herself, consisting of juiced garlic, cayenne pepper and citrus juice, all mixed into water and sprayed. While I haven't used it myself, she swears by it, and says she never has problems killing infestations on her trees. Leaf drop could be due to environment change - from outside to outside, and the scale infestation won't help - they literally leech life from the tree. So first port of call would be getting rid of the adults by hand and the young ones whichever way you choose to do it. Any chance you could show a pic of the roots? If it lifts out easily a pic should be ok to get. What kind of potting media is it in? If it is in poor potting media, I believe that getting it into new, better mix overrides and worries about repotting at different times of year. How this affects flowers and fruits I don't know. How often are you fertilizing? And what watering habits do you have - do you let the mix dry a bit before watering again, or do you keep it moist?
Horticultural oil spray is best for scale and is non-toxic--coat leaves and stems thoroughly. There is no millipede type pest of citrus that I am aware of. When leaves fall without the petiole it is a sign of stress, but when it falls with it, --it is more likely just normal leaf drop. Aesir is right about repotting, if the media is not fast draining with lots of air, you should repot soon. If the tree has outgrown the container (roots circling the inner wall of the pot), then repot. Have you read about WLD--southern exposure can be bad in winter if the roots are not warm!
Thanks for responding aesir22 and skeeter! The container is definitely too small (I can barely pull the root ball out, may have to cut the container) but the soil that was used is good, very well-draining. I will repot and then spray, hopefully the tree won't suffer too much in its new environment...and hopefully it will fruit. I was unaware that there are small/young scale that are mobile? I have only seen the type as shown in my pics... I have read about WLD in past threads...and I bought a thermometer to check root temps..I believe the roots should be kept at or above 65F when exposed to direct sun? Does this mean at night as well or only when getting sun during the day? I'll probably use a heating pad if my inside temp is too low. Hopefully the leaf drop is a result of moving the plant inside or due to the small container size. Any other advice? I love this plant and really hope it survives longer than the 2 year average for container citrus. Many thanks, Rachael
Yeah the little scale are quite good at hiding I have heard, which is why it is important to spray every bit of the stems and leaves - the critters get everywhere! Winter Leaf Drop only occurs when there is sunlight on the leaves and the roots are cold. The light heats the leaves, and the plants normal response is to send water to the leaf to cool it down. But if the roots aren't functioning - which they don't below a certain temp - the water and cannot be transported, and the plant protects itself by dropping the leaf. So, at night if the roots cool a little, the leaves won't drop off. But it takes the soil longer to warm up that the air in your house does, so just because your air is at 70 degrees doesn't mean the soil is. I have the problem that the soil gets a little low at night and takes a bit longer to warm up that I would like, so my citrus are only subjected to partial light first thing in the morning until the soil temps heat up, then they get the good light :) If the roots stay above 60F at night (they stop functioning at 55F but 60F would be better to prevent WLD) you won't have much to worry about I shouldn't think. As for advice...read read read! I only started with citrus this year, but I read almost every thread on here and other forums over a couple of weeks when I had spare time, and you learn tonnes of stuff. Enough to keep your tree alive and happy.
With a soil thermometer, you will see what Aesir pointed out--temp is lowest in morning and generally remains cooler than air temp. When you repot, don't enlarge the container more than a couple inches.
