[happyinthesun]

I am looking to purchase a bird of paradise plant, but is there a particular specie I need to grow on the Costa Blanca?

[Trevor Australis]

What you buy will depend on what space you have, and what nurseries sell. All Strelitzias grow large with age and have incredibly tough root systems, which makes them very difficult to move if you plant the 'wrong' one for the space you have available.
Strelitzia nicholii grows almost as a tree with tall trunks to 4m or so. It has blue and white flowers. Strelitzia reginae is the other species widely grown. There may be other sp. but I don't know them. S. reginae is a large evergreen 'perennial' type plant. It has orange and purple-blue flowers. There are at least three distinct foliage variations: one has large paddle shaped leaf blades, one has much smaller spoon-like leaf blades, and one has no leaf blades at all. Any one of these will take up a significant amount of space after 5-10 yrs growth. In my experience the crowns of plants can easily grow to 3-4 m across, and with the leaf span included up to 6-7m depending on how much the gardener chooses to let the leaves spread.

[happyinthesun]

Thanks for that information I never realised that they grew that big, may have to rethink about this plant and where to plant it

[David Feix]

The form Strelitzia juncea with either small spoonbill foliage or more reed-like stems with no "leaf" at all is much slower growing and unlikely to get too big quickly. Even regular S. reginae is very manageable in containers and much easier to find in nurseries. Here in California there are forms of S. reginae that stay shorter at 3 foot tall, and others that get up to 5~6 feet tall. Personally, I find these look better in a garden setting if foliage clumps are thinned out to show off the grace of the plant's form. Too often they are left unmaintained, and the thicket of dead foliage and densely crowded stems can be unsightly.