getting used to the sun

Because of a lot of direct sun on the windowsill my greenies tend to turn yellow or get pale. When I first bought these bromfieldii v. insularis 'Sulphurea' they seemed to be shocked by the new sunny conditions losing all the green color in favor of yellow. Looks like this year they've learnt how to deal with it. They have a strong chunky shape I like a lot. The color of the newest leaves has also turned out really nice and stays this way even though it's been very hot and sunny. Now only the fulvi 'Aurea' need to understand they won't get any shade no matter how pale they get.
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