Herself's Houston Garden

Conservation through cultivation

Prepping your garden soil

While the climate down here is wonderful for growing a wide range of plants, the soil often leaves much to be desired.  Seems you either get clay or sand if you live in or near Houston.  In our favor organic material breaks down quickly and you can build a nice soil base before too much time goes by.

Proper soil preparation can make all the difference in how well your garden grows.  You will want to work 3″ to 6″ of organic material into your clay or sandy soil before you begin to plant.  You’ll want to work this into the top 12″ of soil.  In addition you will want to add a 3″-4″ layer of pine mulch every year.  Organic material breaks down quickly in our heat.  So you need to keep replenishing it. ( soil amendment materials: pine mulch, compost, peat moss, perlite, sand )

A proper soil test is also needed to tell what fertilizers need to be added.  I’ve found a good time release 10-10-10 4-6 times a year is needed in my yard, spread at about a pound of nitrogen per 1000 sq ft.  I also add a handful ( 1/4 cup ) of iron to each shrub and tree each March.  As organic material breaks down it used up the nitrogen in the soil.  And each and every heavy rain we get washes away a large amount of the nitrogen in the soil.

Drainage is the next issue to consider.  Sandy soil drains rapidly and standing water is not a problem. Adding organic matter will help the sandy soil retain moisture longer.

Clay soils hold water, and even if you improve the top 6″ to 12″ of soil, often the clay underneath retains water.  Adding sand or perlite or both will help.  Before planting watch how quickly the water drains after a heavy rain.  If it takes more than one hour you’ll want to help the drainage with drains.

Plants prefer slightly acidic soils.  While these can occasionally be found in Houston it ‘s more likely your soil pH will be around 8.0 ( slightly basic ).  Changing a soils pH long term by a more than a small amount is unlikely.  But you can add lime ( makes soil more basic ) or sulfur ( makes soil more acidic ) to help.  If you have basic soil add some peat moss each time you plant a new plant to help reduce the soil pH.

Worms help, you can purchase live worms, or as I do add worm castings to your garden each year.  It seems to attract them.  I always find more worms in areas I ‘ve added castings.

If you work clay soil while it is wet, it is likely to compact on you forming a brick like substance that your plant’s roots will be unable to push through.  Wait until the soil it dry to work it.  Or as we did up north lay out 12″ planks and walk/stand/kneel on them to work.

To convert lawn to garden:

1) Apply RoundUp or another weed killer about a week before prepping an area.

2) Scrape off sod

3) Add soil amendments ( 3″-6″ deep ) and work into soil about 12″ deep

The easiest way to work soil additives into the soil is to dig a 12″ trench, then dig a second trench right next to it, filling the first trench with the soil from first plus additives.  Continue trenching your way across your new garden.


1) Apply RoundUp or another suitable weed killer about a week before prepping area

2) Lay newspaper 3-6 sheets thick across entire area

3) Cover newspapers with 6″ of soil, mulch, peat, sand, and compost

Learn more about soil:
Lessons on Soil ( 1911 Russell )
Crops and Methods for Soil Improvement ( 1912 Alva )