The right tablestructure, or is there a better way?

[gerard1979]

I need output like this:
First floor:
behind the door:
1 <plant1>
1 <type1>
in front of window
1 <plant2>
1 <type2>
Second floor:
near to elevator:
1 <plant1>
1 <type1>
and so on.
So I make 3 tables.
tblLocation: location_id, loc_description (first, second floor)
tblSubLocation: subloc_id, loc_id (fk), subloc_description (behind the door, in front of window)
tblDetails: details_id, subloc_id (fk), plant_id, type_id, plant_count, type_count

It seems not to be so difficult, but my problem is:
How can I build a form where people can put the information this way?
In a continuous form it's not possible to make a subform. But I think, I need 2 continuous subforms,
I hope somebody can help me,
Thnx in advance,
Gerard