You could have a personal garden, but to have a farm you'd have to obtain a lot of land. Then you'd have to make the land productive with either large and resource hungry machinery i.e. capital or you'd have to obtain and exploit the labor of farm workers to work by hand.

I don't think most communists would have a problem with people trading crops that they grow themselves. The problem comes in when someone hires employees to grow more crops for them, starts collecting profits, and grows the farm even bigger. All under the expectation that they own everything that their employees worked for. Cause that's literally capitalism on a small scale.

Of course it needs to be possible for multiple people to come together and start growing crops, but only as long as no single person can take over the entire operation. Leaders would be elected, and be given a somewhat higher salary to reflect the additional responsibility.

That's a paddlin'

That requires owning land yourself, which strictly speaking isn't a thing in communism.

Get some LEGOs