The practice of no-till helps to control weeds. This will make sure the soil surface is well covered with plant materials. This is ensured during land preparation, ie. you do not burn and plough.

However, if you didn’t do that during land preparation you can mulch the soil ie. cover the surface with plant materials so the weed seeds do not germinate.

@ebwampah; You further want to know

what chemical can you use to control weed in ginger?

In the case where the weeds have overgrown the ginger (not recommended), you may use a chemical to control the weeds by careful application.

Apply at half the normal rate of application of the chemical and be sure to apply it only at the top where the chemicals with not get to the ginger.

You may use any systemic weedicide eg. glyphosate base weedicide.

This will not eliminate is totally but will make the weeds lighter and easier to remove manually.

Manual weeding is what is recommended after the ginger has sprouted.