Full Sun, Part Sun, Or No Sun???
One of the problems we collectors have is our newly acquired plants come with no care directions, hence we all have to learn the hard way as our specimens either sink or swim where we place them in the warm winter months. Every tag has a backside though, and I believe we need to use it with a suggested lighting environment of full sun, part sun, or no sun (artificial lighting) so that we can minimize our losses and aximize our satisfaction.
Many solid-leaved varieties absolutely love full sun, providing that they are watered and fed regularly. The rosebuds absolutely thrive with the heat of summer, as do most stellars, and zonals in general for that matter. When the forecast is for long hot dry weather, I find it best to water in the mornings and I double check at night. Each plant is different, and some will go semi-dormant in extreme hot weather, so watch that watering. Thankfully in general, plants outdoors are more forgiving of extra watering than indoors. Most golden varieties of plants will tolerate full sun too, but for best results, give them morning or late afternoon sun and they will be much more happy. Miniatures may also be a little weaker than others, so keep an eye on them as you are learning how much sun they prefer.
In my experience, many highly variegated varieties with large white zones prefer partial sun exposure at best. ‘Dolly Varden’, ‘Both’s Beauty’, ‘Chelsea Star’, ‘Don’s Silvapearle’, ‘Chelsea Diane’, and ‘Cherie Bidwell’ are some that come to mind. Many tricolour varieties also may benefit from partial shading including‘Mr Henry Cox’, ‘Ray Bidwell’, and ‘Mrs Pollock’. Common signs that a plant is getting too much light is crisping along the margins and slow growth. Sometimes plants will turn colour when they get too much light, and I find my ‘Ray Bidwell’ turns pink in too much light as I do with a sunburn!
It is hard to believe that some pelargoniums prefer to be kept inside, but I have learned this the hard way over the years through disappointing losses. If you are lucky enough to have any tricolour stellars, please do not put them outdoors! And if you do, keep them under the shelter from the hot afternoon sun and rain. It makes sense when you consider that many plants are weak cultivars with extreme attributes, most especially colouration, and such accessory pigments (or lack of) may make plants very vulnerable to UV radiation. If a plant is developed entirely indoors under lights or inside a climate-controlled greenhouse, we are foolish to assume it will automatically enjoy the great outdoors. Take caution and heed my advice…keep one grow light going in the summer for those weaker plants.
As I hybridize new cultivars, I never really know what type of light a new plant will want at first, so I always keep young plants under lights for quite some time, followed by a long time in a sheltered part-sun location. It is very stressful with new seedlings, because if the months of work pay off, and a beautiful variety is created, the wrong light conditions can stunt or kill off a young plant. I always feel a sigh of relief when I get to the level of sharing cuttings of my new plants with people. There is no better insurance plan than having a trusted friend trial a new variety while you work on multiplying more.
So take some time to look at your plants this summer, and write down which varieties are doing well, along with their lighting location, and you too can have greater success with your collection in subsequent years.
