Without special help of some kind, most plants can only be cultivated between the dates of the last spring frost and the first frost in autumn
There are ways to bypass the weather, however, by giving plants the environment they need to flourish out of season.

Cold Frames can provide the necessary microclimate for plants to be started earlier in spring and allowed to mature deeper into autumn.
These come in traditional wood and Aluminium frames and either plastic or polycarbonate glazing.
Still another way to control the environment is through the use of Cloches.

Cloches (a term that means "bells" in French) have been used extensively in the garden since the 1800's. French gardeners used to place bell-shaped glass jars over individual seedlings to protect them from frost and to give them warm, undisturbed surroundings in which to grow, therefore advancing their crops.

Today’s cloches are made from high quality plastics for the garden they come as single items for seeds or cuttings. 
Tent cloches which cover larger areas are suitable for the garden as they keep delicate plants safe from the environment
For indoors bell cloches are still made from glass and can be used to cover plants or decorative items to keep them safe from  dirt and damage.