You will buy either plants in large pots or in small ones. In either case watering will be critical to their long-term survival. Don’t imagine that you need to water them every day. This will depend on where they are placed. Because our poinsettias will almost certainly come from the USA or from the islands they will be sent in light pots (plastic) and grown in something like Promix. Probably the wisest thing to do to ascertain how much water they have is to lift them up and get a sense of whether they feel light or heavy. Most of us can get a sense of this and it is made all the simpler if you can weigh two at the same time. If you decide they need a drink, do not water them heavily, but just give them an egg-cup full, which will last them for some time unless they are in a breezy situation or exposed to the heat of the sun, both of which will make them use up water more quickly.
Of course when they are growing up to flowering, warmth and good light are essential, but when they are starting to produce their superb scarlet bracts you will get them to last far longer if they are kept cooler. The main idea is to slow things down as far as possible. I would suggest that once you have got a good flowering plant you do not need to apply fertilizer. So finally, keep them on the dry side but not at the point of wilting. Mind you, it is far easier for them to recover from dryness than it is from flooding. More plants are lost through overwatering than any other reason.
For those of you who want a bit of a challenge, once poinsettias have finished their Christmas flowering, then cut them back keeping a well-balanced framework, and repot them in a compost which is loam based. Do not give them massive amounts of food but grow them on slowly in good light keeping them out of the way of breezes and excessive sun heat.
The hibiscus is one of the main plants for the garden, and more words have been written about it than almost any other flowering plant. However, there is one species of hibiscus that is grown almost entirely for fun, and that is Hibiscus mutabilis. Universally known as the Rose of Sharon, when seen in the early morning it is pure white. During the day its colour gradually changes through light pink to a rich pink in the afternoon. It certainly gives one tremendous pleasure and if you can spare the time to place it in the refrigerator when it is still white and bring it out just before your evening meal, it will quickly change from white to pink during the meal.
As the office party season starts, do not forget your plants at home or in the office. Drive carefully and fairly slowly, and wherever you live may your God go with you and keep you and yours safe.