Question
We had a flood in April where our foundation collapsed and three walls of it needed to be replaced.  As a result, we had a lot of heavy equipment all over my property causing the already mostly clay soil to compact.  I replaced my landscaping and planted my usual annuals (petunias, marigolds, gerbera daisies, phlox, etc.).  We then put down sod.  It has been a month since this work has been done.  I have taken a few horticulture classes at Rutgers and learned that overwatering is more dangerous than underwatering.  I cannot convince my husband that he is overwatering our yard (30 minutes each twice a day).  The flowers at ground level aren't thriving.  The ones up in the newly built beds are doing very well.  We are arguing over watering like crazy.  He's going nuts over the brown patches he's developing in his lawn.  I'm telling him it's from overwatering and creating shallow roots and causing the heat of midday to damage the grass more easily.  Is this true?  We are also springing up mushrooms.  He has gone out and purchased a sprinkler that won't reach the upper beds and those look great, just the ground level that gets all this water are looking really poor (smaller leaves, not blooming, etc.) Please help!

Answer
Tara,
In my experience, many people water too shallowly and too frequently. In fact, I just wrote an op-ed piece for our local newspaper about this - you might want to print it out from the website: http://www.capecodonline.com/apps/pbcs.dll/article?AID=/20070801/OPINION/7080103...   (or go to capecodonline.com and search the paper's site for "C.L. Fornari")  Although the part about salt water in the water table doesn't apply to your area, everything else does.

This is the story: in the Northeast, plants are not adapted to a daily rainfall.  If we think about what mother nature provides here, it is rainy periods and dry periods, right?  In places where it rains every day, like in the rainforests, the plants have adapted - they have shallow roots and thick, waxy leaves that shed the frequent downpours.  

In this area, plants need an inch of rain a week, preferably delivered in one long soaking rain.  If they don't get that inch of rain per week, we should be watering in deep soakings but less often.

Every single lawn disease in my turf manual lists TOO MUCH MOISTURE as the contributing factor.  The brown spots may be due to rot or disease, not the lawn drying up.

Also, Japanese beetles and other garden beetles love to lay their eggs in moist soil, so if you keep a lawn wet you will have MORE of a grub problem next year.

Deep soakings promote deep roots that not only let plants go longer between waterings, but deep roots also work to break up clay and improve soil structure.  

Frequent watering causes crown rot and leaf-spot diseases on plants - plants need to dry out so that the roots can have air as well as water!  (Only some plants can grow in a pond....most need water AND air around their roots on a regular basis)

My gardens (very sandy soil with a layer of mulch on top) get watered once every seven days for two hours.  Period.   When I lived in NY state where I had clay soil I would water once every seven to ten days depending on the temperatures - for two to two and a half hours.  

I hope this helps!
C.L.