Lemon seedling trouble!

Hi all! I could really use some help. I started a few Eureka lemon trees from seed and I'm having a little trouble. The leaves are starting to yellow from the edge inward, then dropping. At first i though it was low nitrogen but that doesn't seem to be the case. They are container plants. Any info or tips would be appreciated! Thanks!

How long have you had these plants? I'm not really sure what's causing it, but my plants do this every year, usually when they transition from indoor to outdoor in the spring. It could be a bunch of different micro-nutrients as well as nitrogen, so take a look at this pdf. http://landresources.montana.edu/nm/documents/NM9.pdf This is my standard go-to for plant nutrient deficiencies. I've also attached two pdf files that have charts for various deficiencies. Hopefully one or all of these resources will help.

Where are you? You can add your zone in your profile. And where are you keeping the lemon plants for the winter? Many times, nutritional deficiencies in plants show up when the temperature or water isn't good enough for that kind of plant. Or the symptoms due temperature problems look similar to nutritional deficiencies.

The lemon trees that I kept inside for the winter are also yellowing, but I am just hoping as the weather warms up they'll perk up again. In the house near the windows they are experiencing very chilly temperatures. This is only my second year with the lemon trees, but over the years I've seen many other plants that I overwintered in the unheated greenhouse or on a windowsill had leaves turn yellow or purple, or dry up and fall off, but then they usually recover in springtime.

1.  Too much water.  Particularly in the dormant season.  Cut watering back significantly.

2.  The brown leaf-tips are most likely salt damage.  You need to flush the soil and wash as much of the salt through.  If you've been using synthetic fertilizers, they are high in salt and that accumulates quickly in little pots.


Once citrus is established, most of those problems will go away, but for young trees, you've got to baby them.

Thanks for the responses! I started these from seed about 2 months ago. Thanks for the deficiency charts. They will definitely come in handy! I live in the middle of Kansas in zone 6b. They are kept upstairs by the south facing windows. I supplement lighting due to trees the block the evening sunlight. They're nice and warm, it stays at 72 degrees or higher upstairs. I've watered them as little as possible, letting the soil dry a couple inches before watering again. They've had no fertilizer yet. The only thing I've added to the soil was a little mycorrhizal fungi when I transplanted to larger pots. When should I start fertilizing? Any suggestions on NPK ratios or  brands that has been successful for some of you in the past. Any further feedback would be very helpful. Thanks again everyone!