Destroy Plants from the Grow Overview Page
LeafData might limit the number of plants you can destroy at any one time, so if you get an error telling you to select fewer plants, follow that instruction.
First select the individual plants you want to destroy.
Side note: destroyed clones are not required to be tagged as waste so they're omitted from the waste area.
Then, select the specific plants from that group that you wish to destroy and click 'Destroy Selected'.
Enter the Reason and Explanation for destroying the plants and click "Destroy'". Moving the waste to a specific room is optional.
Destroy Plants from the Plants Page
This can also be done from the Plants page.
Same process. On the plants page, use the filters to find the plants you want to destroy and check the checkbox in the far right hand column to select them. (Pro tip: click the first plant in the list and then use Shift+click on the last plant you want included in the action - that will select all plants in between.) Then click the "Destroy" button.
Now that the items are moved to "Waste" and you can find them in either of these locations:
If you make a mistake, you can go to the Waste window, find the plant(s) you destroyed in error, select them, and click the "Undo Destroy" button:
Once you are fully ready to dispose of these items, follow the steps outlined here.