Your tree does not look like its in dire straits to me. In fact it does look rather healthy.

It COULD use a small amount of pruning to remove the older visibly dead interior and exterior branches. I would also remove a few of the interior branches to help open this area up, and allow for air circulation.

The fruit rotting on the tree looks to me as if it s beyond its ripeness and just doing what its supposed to do. These need to be picked as they ripen or they do what you are seeing. It also appears in the picture of the juicy lemons, that you either have Myers Lemon with severely over ripened lemons, or you have a multi grafted tree with something in the tangerine/tangelo family. Those "lemons" in the back of the picture look way to orange to be true lemons.

The yellowing leaves could be normal. The older leaves usually yellow as they age. Since these are large leaves I would be inclined that they are dying back as nature intended. They have served their purpose. This could also be a sign of root damage if its other than the older leaves being affected.

Lemon trees fruit and flower at the same time. This is perfectly normal.

The "somethings wrong with the leaves" picture shows insect damage and tip burn. To stop the insect damage you can use sevin dust. This will help control chewing insects like grasshoppers and the like. It will also help with orange dog caterpillars, but I usually just pick theses off as I find them. Contrary to the name, the orange dog Caterpillar is not orange, but rather a brownish to gray color. Look closely for these critters.

Tip burn is caused by excess salts in the soil. This can be caused by excessive fertilization and soil that doesn't drain well enough causing the salts not to leach away. Since your tree is planted right next to a concrete foundation, some of the minerals could be leaching out of the concrete and also cause this.

I notice that there appears to be a mulch type berm around the outer edge of the drip line. This could be allowing too much moisture to become trapped around the root ball. This will cause root rot as the roots can not breathe. This needs to be removed. Mulch should not be place under your tree as it holds too much water. I would remove this unless your in an area that really restricts water usage. If this is the case, only apply a 1" layer of mulch and keep it 1 foot away from the trunk of the tree.

Water the tree only when it needs it. Water it deeply and then allow it to dry. Try to keep the water off the trunk of the tree as this will cause a whole slew of other problems.

Fertilize 3 times a year with a good slow release fertilizer with minor elements. 4 times if your area does not receive ANY frost.

Take a soil sample to your local agricultural center for analysis to check for excess salt buildup and get an approximate pH.They can tell you how to adjust if necessary.

Welcome to the strange world of growing citrus and many happy fruitful...

i am giving up on the garden if it weren't for this forum! i can't thank members of this board enough - patient and detailed answers every time! life saver!

so i was worried about the fruit rotting on the tree; cuz i thought if they are ripen they just fall off the tree. so much for my non-existing knowledge of trees :) i did get a lot of comments from coworkers about my lemon looking like an orange! i thought they look normal hehe. when do lemons ripe (meaning when should i pick them if they are now overly wipen)?

i am going to google "tip burn" - no idea what you meant. but we've been in this house for 4 months and it was vacant for half a year so the tree hasn't been fertilized for almost a year. i'll figure out the soil... i'll see if OSH can do an analysis for me! i am in the san francisco bay area so no frost.

i am sorry this is a stupid question, but how do i know the tree "needs water"? my coworkers told me that fruit trees don't need water since they get water from the root...

Normally trees of this size do not need supplemental water unless in a very dry period. You can push a metal or wooden rod into the ground to a depth of 2ft and then pull it back out. Check to see if the rod shows moisture. If it does do not water. If its pretty dry and rain is not expected within the next week or so, I would water it. Water it long enough that when you push the rod into the ground, its wet for the top 6 inches. Being in SF you probably won't need to water as you get a LOT of rain.

Lemons are ripe when they turn yellow and can be picked any time after this. IF your tree is a Meyers Lemon they will eventually turn orange. The Meyers is a cross between a lemon and a Mandarin or orange so it's not a true lemon. You can tell by the taste. Pick one of the "orange" lemons and taste it. You will taste a distinct "orange" type aftertaste. They are also slightly sweeter than the Lisbon or Eureka lemons.

Tip burn is a condition caused by an overabundance of salts in the trees root zone. Fertilizers are salts, so are other components in the soil. If the salts are in to great a concentration it burns the tips of the leaves. Click on the link below to see a picture of tip burn.
Andi

Here is a link that might be useful: {{gwi:575329}}

thanks gardner dragon! i will do the stick test to see if the tree is getting water from the root!

That was a great answer, but I would not say San Fran gets a lot of rain.Granted it's not hot and dry like where I am 45 minutes north and east, so you won't need to water often. but I expect you will need to irrigate some between April and October. Without it I get what I beleieve is chlorosis in the summer, I believe because nutrients can't more well through the dry soil.

thanks nanelle - i am in the south bay area so it's even dryer than SF!

Hello ! I purchased a meyer lemon tree from California several years ago. For 2 years I had blooms and lemon. I live in Connecticut so in the winter I am forced to take it indoors. For the past several years it loses all its leaves then they grow back but no more lemon. This year at a friends advice I took it out of its container and put it in another larger container and cut it down some 2 feet or so as to make it look a little nicer, it was 8 feet tall with straggly. Its been 4 weeks not that it is outside and it looks dead, no leaves and the branches are mostly all brown and brittle. What is happenind, I love my tree but is it dying?
Thank you so much for your help!
Chantal