How do you stop Morning Glory from producing more seeds?

I have this 600 point Biosphere project due soon in science and today's Crisis Day where our groups get a crisis and we have to figure out how to solve it My crisis said "Morning Glory plants appear and population is growing very fast. (seeds were in soil)" I have to figure out how to stop Morning Glory from producing seeds. I've done research but I can't figure it out. And if you tell me to ask my group *sighs* just forget about my group I don't have one. Literally my science teacher didn't put me in a group I'm all alone on this. Please help!