So Ken, you don't have any suggestions as to what can cause the yellowing and brown spots? I just bought these two standards this year. They are in brand new pots with brand new 'storebought' media. The bag from Costco, I do believe. I wasn't clear that the yellowing, brown spots and falling leaves has been a problem since shortly after I bought them in May. After researching online, I thought they might need fertilizing with a liquid fertilizer (I potted them up with Bone Meal Plus, and sprinkled a little Miracle Gro slow release back in May). I don't think giving them a little liquid fertilizer after two months is overdoing it. The bottle says to apply every 8-10 days, and it's been two weeks. I haven't sprayed them yet...just fertilized two weeks ago. I live in the Pacific Northwest, so yes, we have rain in May and June, but July has been a scorcher, think they have been watered consistently, ie not too moist, never completely drying out. They are in a part of the deck that receives morning sun until about noon, I could try giving them more sun...but am hoping someone is familiar with this problem and can help out.

I'm a citrus newbie trying to grow a couple of different citrus trees/plants from seed and it's been going rather well so far. I live up north in Sweden so they're just growing indoors and with artificial light during the darker part of the year. My lemon plant have been the most successful one so far, it's been growing steadily the past year and have looked really healthy. A month ago I pruned it and it immediately started to sprout which was my intention. But today I noticed that two of the new leaves had started to crumble and had yellow spots with brown in them. When taking a closer look I find yellow spots on many of the older leaves as well, but they don't look exactly the same. I've tried to compare the spots against images of citrus pests and diseases, but I can't determine myself the cause. Anyone here with more citrus experience who can help me determine what's happening to my beloved plant? The new leaf, it's more crumbled than on this picture: A few of the older leaves with yellow spots:

The plant needs more light. It's too far from the window. When leaves fall out because the base is brown and soft, the problem is likely to be excessively wet potting mix. You said you water when the surface is dry. How far down is it dry? Stop using fertilizer for now.

My guess would be iron deficiency, or over watering can do it too. Is it on new growth only? There is a lot of good info in this thread http://forums2.gardenweb.com/discussions/1663016/iron-deficiency-in-some-rose-varieties