Customs probably won't have a problem. Check the US Agriculture Dept. they seem to be more interested than Customs when I have come back from abroad. They might not be happy with the hops.
Here, I even looked it up (I am bored):
Fruits, Vegetables, and Plants
Depending on the country of origin, some fruits, vegetables, and plants may be brought into the United States without advance permission, provided they are declared, inspected, and found free of pests. However, certain plants and ANY plant parts intended for growing (propagative) require a phytosanitary certificate in advance. For information on certificates, contact the USDA/APHIS Plant Protection and Quarantine Permit Unit. Also, check the Information Resources section at the end of this notice for details.