GardenBanter.co.uk - View Single Post - Time for pre-emergent? NYC

dgk · 12-03-2008, 01:24 PM posted to alt.home.lawn.garden

On Tue, 11 Mar 2008 10:49:45 -0700 (PDT), wrote:

On Mar 11, 8:22*am, dgk wrote:
On 10 Mar 2008 23:22:56 GMT, Steve wrote:

dgk wrote:

Expense isn't a major factor; the whole lawn is around 500 sq feet. I
think I try the corn gluten, which I'm sure won't hurt the cats. Then,
after a few weeks, I'll throw down some more grass seed, after the
threat of crab grass diminishes.

When is that, the fall? :-)

Ha Ha, but still, a good question. I figured that if a pre-emergent
works on crabgrass but not regular grass, and must, by definition, be
used before crabgrass emerges, then after a certain time interval it
will be safe to stop using it and I can seed regular grass.

From what I read, corn gluten meal works on a physical level by
draining moisture from seeds and cracking them open. Hopefully that
will affect the crabgrass. Then, once the crabgrass seeds are all
desiccated and cracked, I can put down some regular grass seed and
hope for the best.

What you read is pure BS. If it worked by draining moisture, what
would happen if it's rainy and damp for a couple of weeks? You'd
have crabgrass and weeds all over the place.

The explanation I found below makes a lot more sense:

"What makes it work?Once it was determined that corn gluten meal
contained a natural compound or compounds that could inhibit weed
establishment, the next logical step was to determine the nature of
that compound. Graduate student Dianna Liu began this work in 1989.

Liu eventually determined that five individual dipeptides
(combinations of two amino acids) had the ability to inhibit root
formation of germinating seedlings. These dipeptides were glutaminyl-
glutamine, glycinyl-alanine, alaninyl-glutamine, alaninyl-asparagine
and alaninyl-alanine.

ReferencesChristians, N.E. 1993. "The use of corn gluten meal as a
natural preemergence weed control in turf." International Turfgrass
Society Journal 7: 284-290."

And whatever makes it work, it appearntly works for 4-6 weeks. That
means if you apply it at the right time, it's going to be there into
June in NYC. If you start seeding with grass after that, you're in
summer and you're bound for lots of trouble and likely failure. At
the very least, you better have an effective way of applying water and
lots of it through the summer. I'd just wait till Fall which is by
far the best time to seed.

Screwed for another year. I did seed in the fall but none of it seems
to have weathered the winter (such as it was) very well. This grass
growing thing is harder than I would have thought. I'm good with
clover though; I think that means I need more nitrogen. Clover is sort
of nice though. The bees love it.

Something is digging holes in the yard. Not burrows, just around six
or eight inches deep. A lot of them. I think it's squirrels. Could be
a raccoon but we don't have many of those around. Could be a oPossum.
Those are around. Maybe it's time to put in a nice rock garden, a
little waterfall, some assorted elves and flamingos. Put nice flowers
where the tomato plants always die, and put the tomato plants where
the lawn used to be. Arrgh.