Question
QUESTION: Hi, Erin,

I chilled a few apple seeds many months ago, and then planted them indoors in a pot on my windowsill.  Only one sprouted, but it has grown about 4 inches tall now, with a nice little woody-looking stem.  The pot is about 5 inches in diameter, and about 4 inches deep. It has a crown of
about 16 or so leaves at the top, and while the oldest leaves are starting to look like they are changing colors to prepare to drop off, the newest leaves are continue to look vibrant green, and more leaves come periodically.  However, the tree does not seem to be growing taller.  The crown of leaves continues to increase, but the tree does not seem to grow upwards.

I bought a plant light, so the tree has been getting a good spectrum light to make up for the fall lighting from the windowsill.  And I fertilize it every few weeks.  The window
does not get excessively cold, being both insulated, and also mild weather (I live in Atlanta).

I am hesitant about transplanting the tree to a bigger pot, but suspect that it is the small pot size that keeps the top from growing upwards, so would you advise a larger pot?  If so, how large for the first transplant?  And what special precautions, if any, should I observe when transplanting?  (How concerned need I be not to damage some of the finer root hairs?)

Once I do transplant it, how long should I wait before fertilizing it?  And what is the best fertilizer?

Thank you for your time.

Zane

ANSWER: Hello Zane!  Before I completely answer your question, I need a bit more information from you. Do you know what variety of apple you got the seeds from?  What direction is the window your seedling growing in, facing? When did your seedling germinate - i.e. how old is it?  What have you been fertilizing the seedling with and what type of soil is it in?  How far above the seedling is the plant light and what kind of plant light is it - fluorescent, sodium, HID, etc?
  First, apple trees are pretty slow-growing.  If you got the seed from a store-bought or hybrid apple, the fact that only one germinated hasn't anything to do with your care. Hybrid apples have been crossed (hybridized) and crossed again so many times, that it's common for all of the seeds in a hybrid apple to be sterile and unable to germinate.
  For potting up, or putting the seedling in a larger pot, go only one or two sizes larger, and be sure to put the seedling at the same depth as it is in its current pot.  Apple trees have quite shallow root systems and it's a rule of thumb to never plant a tree to deeply.  Do your best not to disturb the seedling's small roots - these are its feeder roots - and harming them can set the seedling's growth back.
  You might want to not fertilize so often: but I can't say until I find out the type of soil the seedling's in and the fertilizer you're using.
   I look forward to hearing from you, so I can give you a more complete answer.  So far, though, you're doing a great job - don't despair, Zane!
Erin

---------- FOLLOW-UP ----------

QUESTION: Thank you for your reply, Erin.

The apple seed came, I think, from a Macintosh, which happens to be my favorite.  

The window is facing West.

The seedling germinated in the Spring 2007.  

I've been fertilizing with an all-purpose Miracle Gro, which I think is 15-30-15

The soil is general potting soil.

The plant is about 9 inches below the plant light.  The light is a 75 watt incandescent plant bulb that I purchased from Home Depot. It's not one of the round gro-light type bulbs. It is a one of those wide lights where the front is almost flat-looking.  Something like the one in this ad:
http://www.acehardwareoutlet.com/(23cm0045ocvxui55anixhmfr)/ProductDetails.aspx?SKU=998019594

I hope that is enough info.  Thank you again for your help.

Zane

Answer
Hi Zane,
Thank you for the additional information. As I said in my last email, apple trees are fairly slow-growers.  It takes upwards of 10 years to get edible fruit from an apple tree grown from seed.  However, the sheer satisfaction of eating a fruit off of a tree which you've nurtured from seed, is a joy that few can claim!
   To hasten the tree's growth, you can do the following when possible:  1.Put the plant in a south-facing window or under a plant light which is kept at about 2-4 inches above the plant. If you can hold your hand between the light and the seedling for more than 10 seconds, the light isn't too hot for the seedling.  2. Follow your original plan of moving the seedling up to a larger pot. You are absolutely correct that the plant needs a bit more space! Fruit trees will usually break a slow growth habit when they're potted up. When potting-up, always use a pot that is only 1-2 sizes larger than the current pot.  Your plant is now in a pot around 5 inches across and 4 inches deep.  The new pot should be about 7 inches wide and 6 inches deep, or the nearest size to those dimensions that you can get. This will keep your seedling from suffering too much transplanting stress.  3.  Feed the plant with 1/4 strength of the fertilizer you're now using, and water only when you insert a finger up to the second knuckle into the plant's soil and your finger feels dry.  If it feels moist, it's too early to water.
It's best to water all indoor plants using the "2-knuckle test" because light, temperature and humidity will all change slightly indoors. So, watering on a regular schedule puts plants at risk of over or under watering, and both can make plants succesptible to pests and diseases.  4.  Try the following fertilizer recipe for faster, healthier growth: 1 Tbl. liquid or dry kelp/seaweed (save money by going to a health food store and buying powdered kelp. It's very inexpensive. Just mix it with water until it's the consistency of thin buttermilk.), 1 tsp. Blackstrap molasses, 1 Tbl.willow tea, 1 gallon of water. (The willow tea is made by taking a twig of willow - any kind - and cut it into 1 inch bits.  Soak it in boiling water for a couple of hours or at least until it cools completely. Strain out the twigs.) Put the fertilizer into a spray bottle and spray the plant's leaves, both top and undersides. You can water your seedling with this mix, as well.  The kelp has high amounts of nutrients, natural plant growth hormones, trace minerals and has been found to make plants more pest and disease resistant. Willow contains natural plant growth stimulating hormones. The molasses contains iron, sulfur and simple sugars which nourish the plant.
 Hope this helps! Let me know how your tree comes along. Remember it won't be like its mother fruit tree, but a new variety of apple with some Mac qualities, depending on what type of tree pollinated it.  Any way you look at it, though, you're getting the pleasure of a new friend who fruits and can live to be over 100 years old!  Enjoy!
Erin