How is it that you used a herbicide to get deep rooted weeds and then immediately planted new plants?
I presume to kill the weeds so the plants have clean ground without competition.
I also presume the new plants were not susceptible to the herbicide used per label instructions.
sig: if this is a new economy, how come they still want my old-fashioned money?
The problem with these "crasher" type shows is they are trying to get everything done in a day or two so corners are cut. Watch these shows for the overall idea not the techniques.
Round-Up sprayed on the leaves of existing plants won't affect the new plants as long as the Round-Up is dry before the new plants are set. If you have a weed that is growing up through a bush that you can't pull you can give it a "Round-Up Handshake" to kill it without killing the other plant. You take a rag or a glove and wet it with Round Up and wipe it on the plant you want to kill while avoiding the plant you don't want to kill. In a day or two the weed will be dead.
Any advice given here is general in nature and is not necessarily valid for your given area. If in doubt check with your local codes enforcement department for what is required when doing electrical, plumbing or structural work on your house. Permits may or may not be required in your area and home owners may not be able to DIY some tasks. I have no way of knowing if you have the skills needed to complete the tasks you are asking about, when in doubt seek professional assistance.
My advice may be worth exactly what you pay me for it. :-) For the record I did not stay in a Holiday Inn Express last night.
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