I have had several different coloured dwarf Alstroemeria which I have tried to grow in pots. These always seem to die right back just as they are about to flower. I have moved them into the garden this year, but unfortunately, the same thing has happened to 2 of the plants, the 3rd has produced some flowers and the 4th is still green, but none are thriving or lush with flowers. What do you recommend?
While Alstroemeria are reasonably straight-forward plants to cultivate and provide masses of flowers for indoor display, there are occasions when they do not perform to their full potential.
Although not overly fussy about the soil they grow in, they are certainly more successful in a fertile well-drained soil to which compost and/or planting mix has added and combined well. While preferring a full sun site, they can also grow well in a dappled light position.
With the Alstroemeria you have described; at this time of the year, we would suggest cutting off all the green growth, dividing the plants and replanting in a well-drained site with soil prepared as above. If they have not shown vigorous growth by 2-3 weeks, remove and replace with new specimens.