How Much Mix (or Medium) Do I Need?

We are often asked “How much mix (or medium) should I buy to fill my 5 gallon Smart Pot?” Or my 10 gallon? Or my three – 7 gallons and one 30 gallon? Planning ahead for this question will make container gardening much, much easier – and a lot more fun!

Container gardeners need to consider – Should I buy a few bags of mix, or am I putting out enough Smart Pot containers that I should perhaps buy a load of mix?

Depending on the size of your container garden (find out what size container to use), you may want to consider buying a load of mix as opposed to buying a large number of 50 pound bags of mix. Many grow or hydroponic stores, landscape supply stores and/or garden stores sell mix in bulk. Some will deliver to your back yard, while others will load the mix into your pick-up at their place. Purchasing mix by the load is almost always less expensive than buying separate smaller bags.

Mix is sold in bulk in Cubic Yards. The minimum amount sold is usually about ¾ of a cubic yard, although this varies depending on the supplier. Multiply the number of Smart Pots you plan to purchase by the cubic yard volume. If the volume of mix needed approaches or exceeds ½ of a cubic yard, you should consider buying in bulk.

Following is an approximate volume chart to help you decide if purchasing mix in bulk is a good idea.


Smart Pot Gallon SizeVolume in Cubic YardsVolume in Cubic Feet
1-Gallon0.0050.13
2-Gallon0.0100.26
3-Gallon0.0150.40
5-Gallon0.0250.66
7-Gallon0.0350.93
10-Gallon0.0501.33
15-Gallon0.0752.00
20-Gallon0.1002.67
25-Gallon0.1253.34
30-Gallon0.1504.01
45-Gallon0.2256.01
65-Gallon0.3258.69
100-Gallon0.50013.37
200-Gallon1.00026.74
300-Gallon1.50040.11
400-Gallon2.00053.48

Not sure what size Smart Pot container to use?

We can help you with that.