Trimming oleanders to get fill in between them?

Question

I have a row of 15 oleanders that were planted about two years ago at about 5 to 6 feet apart where they should have been planted at 4 feet apart. How and should I trim the branches BETWEEN THEM to get better fill in or encourage growth? Some of the plants do not have lower branch growth from the bottom to the side?

Answer 1

If you have full size oleanders and not a dwarf variety then 5 to 6 feet spacing will be perfect in time. 2 years is young and not nearly developed.
Water an fertilizer will stimulate growth. Shaping the tops down a little may stimulate lateral growth.
Lower branch growth depends on sunlight to the lower part of the plant, adequate water and nutrients, and maybe pest control if there are aphids or scale insects feeding.