Question
My wife and I sem to have a hard time getting our squash to grow into mature plants. The palnts coem up looking healthly and all but then at the bottom of the plants they to rot and die. We fertilized the plants, water once a day to every other day, use dietamation earth around the plants but they always seems to rot out before we can get any rewards from our efforts.

Answer
Harold, although it is very difficult to provide an absolute diagnosis remotely, I can give you several conditions that result in the same symptoms you have described.

The most likely cause is a disease called Bacterial Wilt.  Although it is generally spread through cucumber beetles, it can also be soilborne.  These 1" yellow beetles, which are either spotted or striped, carry the disease and spread it from plant to plant.  The leaves eventually yellow and the plant wilts literally overnight.

A second possibility is the squash vine borer.  These pests tunnel into stems and cause the plant to wilt and die.  They are very difficult to detect since they remain inside the stem.  The best way to detect them is to look for yellow, sawdust droppings near the base of the plant.

The third insect that attacks squash is the squash bug.  They are grayish-brown and are 3/4" in length.  They suck juice from the leaves which once again causes the plant to wilt and perish.  All three of these pests can be controlled with organic pesticides or chemicals.

BT is the only insecticide that controls the borer. Unfortunately, it must be injected into the stem to kill the borer.  Many gardeners wrap their squash vines with aluminum foil to prevent the borers fron entering the vine.

Squash bugs and cucumber beetles can both be controlled with organic pesticides such as pyrethrum or rotenone.  Sevin, a harsh chemical, is also very effective.  The advantage of using organic controls is that you can spray right up until the day of harvest with no danger to you or your family.  You should never spray chemicals such as Sevin within two weeks of harvesting.

One disease that can be contracted and is not spread by insects is Downy Mildew.  This disease will cause the leaves to yellow and eventually fall.  Regular spraying of a copper fungicide will prevent this disease as long as you begin spraying in early July once every two weeks.

The best advice I can give you for next year is to first rotate your crops.  Do not plant your squash in this same area for at least two years.  Otherwise, the disease will resurface.

Secondly, cover your crops in spring with reemay, otherwise known as row covers.  Reemay is a fleece-like material that protects the plants from insects and frost.  It is very lightweight and porous. Therefore, it lets water and light in, but keeps pests out.

I hope this answered your question.  Please write again if I can ever be of assistance.

Regards,

Mike