Good light is essential for Neoregelias to bring out those wonderful colors they are so well renown for.
Though many Bromeliads are originally children of the tropics and sub-tropics, they are very adaptable given the basic requirements.Adaptability to temperature and light vary from species to species and genus to genus. Whilst there is no easy rule of thumb it is simply too diverse, many Bromeliads are easy care and other have special needs.
The intensity of light can totally change the appearance of a plant. Though temperature is important it is not as crucial as light. Many Bromeliads can tolerate temps. of 5-10 for several days but frost for more than a couple of hours can be fatal to many species. For those who wish to grow Bromeliads in these temps careful choices of plants is required.[refer to my post June 21.07+ cold tolerant plants] As mentioned there is no rule of thumb various aspects must be taken into consideration like wind, relative humidity etc...
The physical state of plant and nutritional status plays a major roll in cold resistance and adaptability as well as the plants past exposure to correct lighting. Young foliage being generally more susceptible than older foliage. Neoregelias that have soft green leggy foliage resulting from over fertilization and, or, grown in insufficient light suffer a great deal more cold stress. The cells in these leaves have weak walls leaving them weak with lack of resistance to adverse conditions. These plants require extra care to bring them back to their ideal conditions. Needless to say.....
Prevention is better than cure,
The ideal solution is to have all your plants in good physical state prior to the onset of the colder weather. High nitrogen levels in plants drastically reduce plant resistance. Potassium [potash] and calcium dramatically increase plants cold resistance. The latter having the effect of strengthening cell walls, producing good strong leaf growth and color. May it be added that all 3 elements are of important to growth in a correct balance, in moderation and high nitrogen fertilizers should be avoided by all Neoregelia growers.
Timing is important. Fertilizers are best applied to young fully rooted plants in spring. This gives the plant time to produce lush new growth for summer and harden off sufficiently before the cold sets in.one application is usually sufficient depending on the health status of the plant. A lot of Bromeliads are beautifully grown in New Zealand and good reference for those in cooler areas is in a book put out by Andrew Steens author of 'Bromeliads for the contemporary garden'.
Having said this...there is a Bromeliad for every situation and many are easy to grow and bring rewarding easy care beauty to every garden.
***Photo shows comparison of the same plant grown in good light and pup.The green plant has been subject to adverse conditions...lack of light,Full sun during our winter months is ideal, with protection from the really hot mid summer western sun.