Q.Buddleia leaves turning yellow
I have a Buzz Magenta Buddleia , in a large pot. I used some compost and lots of agri grit when planting up , but the leaves are turning yellow. this years growth seems ok atm but last years leaves ( smaller and nearer the base) are really bad and falling off. Any ideas? Can i take it out of the pot to see if it’s water logged without damaging the new growth ( nearly ready to flower)?
Compost alone may not be a good growing medium. A good potting soil can be amended with some compost. Yes, you can try repotting to correct the soil.
Watering issues; too much or too little can also cause yellowing leaves.
The link below will help you access the care.
https://www.gardeningknowhow.com/ornamental/shrubs/butterfly-bush/butterfly-bush-container-care.htm