-The weather in Toronto has been very hot recently, (35°-40°) so I've been keeping it outside everyday for 6-7 hours in direct sun. I bring it inside during the night or in the evening when the sun is gone. - One day, I randomly noticed 2 tiny black spiders on the leaves which I had never seen before. I instantly removed them. Then, today, again, I saw another spider. I was left a little confused as to how they got onto my tree. - Water is given every 2 days or when the soil is dry. Leaves are also misted often. - A couple weeks ago, I added some citrus fertilizer spike to give it nutrients. - Lemon tree is fairly young and is potted. -some of the older leaves are becoming discolored (light green) and some are breaking off.
Since it only gets 8 hours of sun per day, I would be willing to bet that some of the older leaves are falling off to conserve energy. This can happen when the tree is at its lower limit of light. Likely, it will not cause an issue. Some leaf drop is normal. Just be sure that you keep the soil moist down past 10 cm. Let it dry pretty well above that point. This balance can be tricky, but can be perfected with practice.
Be sure to follow all instructions on the fertilizer package to avoid overfeeding.
Here is an article that will help you to care for the tree:
https://www.gardeningknowhow.com/edible/fruits/lemons/growing-lemon-trees-containers.htm
How often should I fertilize Meyer lemons and what are the preferred months.
This article should help:
https://www.gardeningknowhow.com/edible/fruits/lemons/learn-about-fertilizer-for-a-lemon-tree.htm
I got my tree in July and it was doing great. Once Temps dropped below 50 degrees I brought it indoors and it started losing leaves. I saw what looked like a few mites so I purchased neem oil and made a mixture of neem, water, and dawn dish soap and have sprayed it twice, one week apart. My tree is nearly naked. I'm only watering it once a week. It's only been indoors for about 3 weeks if that. After I purchased it and gave it a bigger pot it started growing quickly and all the new leaves were much larger than the existing ones, I'm not sure if that's normal either. Please help.
Citrus will go into shock if their environment changes too quickly. Add a mite infestation and harsh treatment with Neem oil, and you have a recipe for a very unhappy tree. On top of this, repotting stress is difficult for a tree to recover from, and takes more time than your average plant.
Altogether, the stress has rendered the tree in rough shape.
If you have everything under control, then care for it perfectly until it can return outside. Make sure to, only, water when it needs it and not on any schedule. The soil should dry out, thoroughly, down to about 2 or 3 inches between waterings.
Here are some articles that will help:
https://www.gardeningknowhow.com/special/greenhouses/grow-light-terminology.htm
https://www.gardeningknowhow.com/edible/fruits/citrus/growing-citrus-trees-indoors.htm
https://www.gardeningknowhow.com/edible/fruits/lemons/growing-meyer-lemons.htm
My myer lemon tree indoors has a lot of flowers but there is no smell thes year. Past years have had wonderful scent.
If the tree isn't fertilized, frequently, then this could be why.
https://www.gardeningknowhow.com/edible/fruits/lemons/growing-meyer-lemons.htm
Bought one but it is 3' tall & the catalog shows a 2' well branched bush. I'm afraid it will die if I just cut it at 1', can I graft it there (own stock) and prune the main trunk when the graft shows growth?
Lemon trees do not need much pruning. You can remove any dead, damaged, or broken stems at any time. These articles should help:
https://extension.umd.edu/resource/growing-dwarf-citrus
https://today.oregonstate.edu/news/pucker-it%E2%80%99s-time-talk-lemons
https://www.gardeningknowhow.com/edible/fruits/lemons/lemon-tree-pruning.htm
How long does it take for a Myer lemon tree to start producing fruit?
If your tree is grafted, it can bear fruit in two years. If it is seed grown, it can take 3 to 5 years to bear fruit. Here is info on pruning:
https://extension.umd.edu/hgic/topics/growing-dwarf-citrus
https://www.gardeningknowhow.com/edible/fruits/lemons/growing-meyer-lemons.htm
How do I treat the tree? What do I need to do to produce more fruit?
It looks like a nice setup. Does your tree get outside in the summer? If not, you have pollination issues. Here are articles that should help:
https://www.gardeningknowhow.com/edible/fruits/citrus/citrus-fruit-brown-rot.htm
https://www.gardeningknowhow.com/edible/fruits/citrus/citrus-alternaria-rot.htm
https://www.gardeningknowhow.com/edible/fruits/lemons/growing-lemon-trees-containers.htm
https://www.gardeningknowhow.com/edible/fruits/lemons/hand-pollinating-lemons.htm
https://www.gardeningknowhow.com/edible/fruits/citrus/growing-citrus-trees-indoors.htm