Question
Kenneth,

Thanks in advance for your response to this.

I have a few concerns about my lawn. First, let me put it in context. I live in Stockton, CA so it gets hot here in the summer and rains in the winter.

#1: I have poor drainage in my backyard and the grass grows sparsely in the lowest spot. I cannot water the low spot independently so that is not an option. Would granual gypsum help?

#2: What type of seed should I use in this area and when should I seed? It's probably too cold now to get proper germination.

#3: What should I be doing this time of year?

Thanks again.

Rick Wesch

Answer
To answer your second question first:
- use the same grass types as you have today. If you grow warm season grass (bermuda, st. augustine, bahia) then continue with same, or if you grow fescue or kentucky bluegrass then use same.

- poor drainage is going to be a problem for any grass type and unless you remedy this situation, you will not have luck with any grass type. Gypsum is not a good solution unless mixed into the soil in generous amounts and then only if the problem is a high sodium clay soil (does not work on all clay types and does not help if purely topdressed).

My recommendation is to till the ground to a dept of 12-18" and install a drainage pipe at the bottom of a trench. You can use a "big-O" pipe (performated large diameter plastic pipe) which you wrap in landscape fabric and place at the bottom of a dug trench. Lay the pipe on a bed of small rocks about 6-8" deep. A 1-2" drop per 10 linera feet is fine (e.g. a 5"-10" drop over a length of 50-60 feet is good).

If you have no where to drain the pipe to, then you can also dig a large "well". Dig a 3 feet long x 3 feet wide x 2-3 feet deep well. Place landscape fabric at bottom and then large rocks in this well (here the larger the better). Wrap the rocks in landscape fabric (to avoid silthing) and cover with atleast 8-12" of soil. You can also run the above pipe into this trench.

Remember to leave about 8-12" of soil above pipe and trench to avoid yellowing of grass above it.

Good luck.

By the way:
- if you sow cool season grass seeds (kentucky bluegrass, fescue) do so in late spring or early fall. Early fall is going to give best result for warm season areas like yours.
- if you plant (plug or sod) warm season grass like bermuda, st. augustine, or bahia then do so in early summer. Do not plant warm season grass in fall.