It is possible, but you'll have to become a master of amino acid contents (knowing which foods contain/lack which aminos) so that you can ingest the equivalent of complete protein.
Too bad hemp messes the OP up. I eat chlorella and spirulina at least once a day.
Hemp wiki
Hempseed's amino acid profile is close to "complete" when compared to more common sources of proteins such as meat, milk, eggs and soy.[11] Hemp protein contains all 21 known amino acids, including the 9 essential ones[12] adult bodies cannot produce.