Improving Garden Soil
I have about a 35x50 garden and the majority of the dirt in it is a red sandy clay. Its not awful when it is wet, but after time, its very sticky and Im not sure my vegetables are doing as well as they could. I have mulched it heavily, but NOT mixed it in. I dont want to create a nitrogen deficiency. I used to till it regularly, but have adopted a no till type of program to see if soil structure improves. Soil tests come back with proper levels of nutrients, but a pH of 7.8. Should I amend the soil or just let the mulch break down on top after many years? If I should amend it, what should I amend it with in order to make it more suitable for vegetables?
Waller County Texas soil and fertility issues
With the red clay parent material of your soil, I recommend using the EarthKind Soil System. Rake the mulch to the side and then add 3-4 inches of finished compost and 2 inches of expanded shale. Till to a depth of 8 inches if possible. Plant the vegetables and remover with 3-4 inches of mulch. Now you can allow the mulch to decompose and add nutrients to your soil. Each year uncover the mulch where you are going to plant, add nutrients per soil test, plant and recover.
Minimizing tillage allows the soil to rebuild structure and tilth.
Heavy mulching is often a great mechanism to reduce weed competition and reduce water evaporation, however if your mulch is too heavy, you can also limit air infiltration. I suggest preforming a light tillage operation to reduce the mulch layer. You can always add supplemental nitrogen if you see slow growing plants or yellowing lower leaves. The long term goal should be to encourage as much year round root growth, consider planning cover crops, such as a clover in your off seasons. Provided you have adequate moisture, the root activity will improve water and air filtration and allow for better vegetable plant root growth, and also development of soil structure that is often lost due to excessive tillage in our gardens.