I'm also fairly new to growing chufa myself but I can share what I've learned from the master chufa grower PCP on this site.

I would do a burn down of the grass and any broad leaf prior to planting. I'd use a 2% or 3% solution of generic gly for the grass and 2,4D for broad leaf. I use 4 oz. of Milestone just because I have some on hand. However, Milestone is very expensive so I would go with 2,4D. After you spray wait a few weeks for everything to die. When good a dead prepare a good seed bed, broadcast 200# to 300# of a quality fertilize per acre. I personally use 17-17-17. Broadcast 50# of chufa seed to the acre and cover lightly cover with disc or drag. If you are using a planter or grain drill you can get a little more acreage per bag of seed. At 60 days growth fertilize again with 100# per acre of ammonia nitrate 36-0-0.

If this is a new site you are planting you will most likely have few issues with grass if you do a good burn down prior to plating. If you do have a grass issues you will need to spray your established chufa with Clethodim used with an nonionic surfactant....do not use crop oil with clethodim on chufa. If you have broad leaf issues you will need to buy Milstone. I personally use 4 oz. mixed in with my Clethodim and spray for both grass and broad leaf at the same time.

End of June through mid July is the preferred planting dates for most folks.