Variegation, which plants for more light, which for less
I know this is old school, but I have a passage of text from a book to consider, not a link. Unfortunately the book seems entirely focused on outdoor in-ground planting, but this general info should also be relevant to plants in pots. The blue part is copied from Variegated Plants; The Encyclopedia of Patterned Foliage by Susan Conder:
Variegated plants originate naturally as random seedlings, or as sports - mutant variegated shoots on otherwise plain green plants. Some, such as Abutilon pictum 'Thompsonii', are virus-induced, in the same way that the streaked colours of 'Bizarre' tulips result from a harmless virus.
In red-or purple-variegated plants, chlorophyll, the green pigment responsible for photosynthesis and vital for non-parasitic plants' survival, is masked by other pigments, anthocyanins. Yellow and white variegations are caused by imperfect or absent chloroplasts, the granule-like plastids within a cell which contain chlorophyll.
In a white- or yellow-edged leaf, the green pigment functions normally in the inner layer of leaf cells, but the outer layer lacks chloroplasts, making the edges white, or contains a preliminary version of chlorophyll, protochlorophyll, creating yellow.
A yellow- or white-centered leaf, with green edges, has a defective inner layer of leaf cells. The attractive pink, red or russet spring flushes that some variegated leaves have result from anthocyanins protecting the vulnerable new growth from harsh ultraviolet light rays. Autumnal flushes result from an accumulation of sugar in the leaf tissues, caused by a drop in night temperatures which triggers the production of anthocyanins and anthoxanthins.
(All great stuff, but here's where I think it gets really interesting - and useful.)
The intensity of leaf colour is affected by the amount of light available. There are exceptions, but generally, variegated plants with glaucous foliage, such as rue and certain hostas, tolerate more sun than all-green kinds. Those with purple, maroon and brown variegations colour most intensely in sun, often becoming dirty green in shade. Yellow-variegated leaves colour best in full sun or light shade. White- and cream-variegated leaves, such as variegated apple mint, tend to prefer shade, especially where the soil is dry. With those that are happy in sun or shade, variegation is often sharpest in sun, but if it is combined with dry soil, smaller leaves and more compact growth result."
So, in a nutshell, some plants are more colorful or pronounced in shade and others in more sun. So which plants do you have that are as colorful as "the pictures out there?" And what is their sun situation? Any other general variegation comments? I love the way the same Coleus plants will look totally different in sun vs. shade.
For the 2 kinds of Dracaena marginata trees I have, I've seen the best colors with more sun, a few hours direct, time of day doesn't seem to matter.
I don't know if my older Sans leaves faded because that's what old leaves always do or from not enough sun for years at a time periodically. This year I put them out in a ton of sun and they are making tons of babies that are very distinctly variegated, so pretty and not the boring plant I thought it was all this time.
The maroon-ish Tradescantia zebrina I have seems to get darker in full sun but the grayish-green stripes get lost. When in enough shade to see the lines clearly, the overall color looks faded to me. I'd say this one depends on preference and available locations.