Where are you (geographic location), when were they planted and how often are you watering? And any other details you care to provide re: soil conditions, amount of sunlight, current temps. etc.

Southern California/Orange County - USDA Hardiness Zone 10a. I believe both are watered via sprinkler about every 3-4 days? Clay soil. Full sun - on east side of house. Temps here are always moderate - high 60s to low 80s day; high 50s to low 60s at night.

Lavender needs very little water while the duranta likes quite a bit. If they are too close together, one or the other will not be happy depending on the amount and duration of the irrigation. Or both, if too much for the lavender yet not enough for the duranta.

Whatever is the issue - and I do suspect it is watering - it is not a disease or insect problem.

Watering - that's good. Guess we'll have to hand-water the duranta on the non-sprinkler days. Thank you!

you need to learn how to insert finger and FIND OUT when your plants need water ... and/or when your soil needs water ... you have to learn how to NOT guess ...

every 3 or 4 days.. may or may not be good enough ... and that is why relying on lawn sprinklers or some such.. often fails ...

once you figure out how moisture moves thru your soil.. you might be able to use an automated system ... but then you will have the problem of some of the plants being too wet.. and others too dry ...

so.. i suspect transplant shock.. related to less than stellar watering ...[you didnt really tell us when they were planted]

but 2 thumbs up for noting the new growth is unaffected ... and .. to me.. that means you are close to getting it right .... if new growth was impacted.. you would be looking at serious problems ...

btw .. once fully established ... once they have gotten over transplant shock.. you may have to adjust watering again ...

ken