Thanks Dave, yes I understand it would be impossible to represent every possible value into a pulldown menu. But maybe rounded up figures would do, heights of plants can be very variable too according to growing conditions...
Maybe something like this..with the corresponding centimeters between parentheses
1 - 3 inches
3 - 10 inches
10 - 20 inches
20- 30 inches
30- 40 inches
40- 50 inches
50-60 inches
60-70 inches
70-80 inches
80-90 inches
90-100 inches
I think there are not many taller than that except the trees of course!
And there could be the possibility to cross on more than one for the same plant..
A pull-down menu would be more handy to fill in too I think..