Q: I want to start a vegetable garden in a pasture with bermudagrass. I want to go ahead and plow it up now and add some leaves and compost to sit over the next few months, but feel I need to kill the bermudagrass first. I would like something organic to kill the grass. Do you have any suggestions?
A: You have a world of education and work before you! The most important thing you will learn is how difficult it is to kill bermudagrass. But I know you’re smart because you thought about killing it BEFORE you planted, rather than afterward.
I would not plant a garden until I was SURE all bermudagrass was dead….and that will take at least three months.
Here’s what I’d do:
1. Identify the spot where you want to plant. Double its size just in case you decide to expand your garden in the future. Mark a perimeter twenty feet outside the boundaries of the plot.
2. Wait until the bermuda is fully green this spring. Spray the whole plot thoroughly with Roundup Pro(tm). There is no organic weed killer or technique that will kill bermudagrass but the ingredient in Roundup has a very good environmental profile.
3. Wait thirty days for surviving bermudagrass to sprout. Spray again.
4. Wait seven days and then till or plow the plot. Mix in your compost and lime, if needed, to improve the soil
5. Wait thirty days to see what weeds sprout up from seed or roots. Spray again.
6. Wait seven days and you can plant, finally. You’ll still have time to harvest plenty of tomatoes, beans and squash before frost.
7. If you subsequently notice bermudagrass sprouts, mark the spot with a plastic flag, spray with Roundup and inspect again in a few weeks.
DO NOT underestimate bermudagrass. It is EXTREMELY invasive in a garden. You’ll save a world of woe if you make sure it is gone before you plant the first seed.