Loam is a necessary garden clay mix that is easy and inexpensive to prepare.
Autumn is the time of year to start separating your water lilies. This means you must have garden loam for your soil medium. Regular potting soil will not work, because it is light weight and will float to the water surface - making your pond very dirty!
Step 1: Loam Ingredients
2 parts clay soil
Can be found at a sand and gravel yard, your backyard, or near a river or lake.
1 part river sand (not ocean sand)
Can be found at a sand and gravel yard or near a river or lake. You can also purchase "playground" sand from a hardware store. Make sure it is not sand used for concrete. The best sand is the kind that has flecks of iron pyrite (which is not in playground sand). River sand often has iron pyrite. Sand and gravel yards also carry river sand.
1/2 to 1 part pea gravel or silt (optional)
Can be found near a river or lake, and your local hardware store. I do not care for pea gravel, because it makes it difficult to fertilize the lily plant.
Cost for a 5 gallon bucket of clay soil and a 5 gallon bucket of river sand from the sand and gravel yard = $6. This is a great deal, because it is far more expensive if you buy it already mixed from a nursery.