Make Your Own Fertilizer
Here are several homemade recipes to try:
1. Magnesium-Loving Epsom Salt Fertilizer
Combine 1 T epsom salt to 1 gallon of water.  Water your plants with this once a
month or however often you feel necessary. 
Tomatoes, roses, houseplants, potatoes, and peppers all love magnesium

2. Fish Tank Water Fertilizer
Use this in place of any fertlizer!  Full of nitrogen that every plant needs!
Is your soil too alkaline?

3. Coffee Ground Fertilizer
Spread your used coffee grounds on newspaper on a cookie sheet and allow
them to dry completely.  Sprinkle the grounds around the base of your acid-loving
plants.  Blueberries, roses, rhododendrons and Azaleas love these, but be
careful not to overdo it.  Put the used filter in the compost bin.
Coffee grounds are filled with nitrogen, magnesium, and potassium.

4. Vinegar Fertilizer
Combine 1 T to 1 gallon of water and water your garden every 3 months.  The
acetic acid in vinegar will increase the acidity for those acid-lovin' houseplants.
 
Soil too acidic? Use these instead of buying agricultural lime.
5. Egg Shell Fertilizer
Let your egg shells dry.  You can put them in a plastic bag and beat them with
something until they are broken into tiny pieces, or if you want to get fancy, put
them in a blender.  Sprinkle them in your garden.  Because egg shells are mostly
calcium carbonate, you can use this in place of agricultural lime.

6. Fireplace Ash Fertilizer
Sprinkle your wood-burned ashes in your garden beds and work into soil.  Do not
use around acid-loving plants.  These ashes are rich in potassium and calcium
carbonate.