Bougainvilleas are drought resistant, free from pests and disease, romantic, glowingly colorful, and easy to grow — but not easy to plant or get started. Use them as large ground covers on banks and have them pouring over walls, roofs, fences, and arbors. Here is the best way to plant them.

Choose plants with the color, eventual size, and growth habits you desire in mind. Some are vines and some are shrubs. Some are more vigorous than others. Five-gallon size plants make a faster start in the ground than the one-gallon size.

Choose a spot in full sun, preferably where the root run — the area where the roots grow — is also hit by full sun. (In the desert and hot areas of the country, bougainvilleas will bloom in light shade.)

Dig a hole twice as wide as the container and the same depth as the container. Loosen the soil in the bottom of the hole, and work in 2 or 3 cupfuls of bone meal. (If the soil is heavy also work in gypsum.) Cover this with enough soil that, when you set in the plant, the top of the root ball will be level with the surrounding ground. Add slow-release fertilizer tablets, according to package directions, around the bottom of the hole.

Bougainvilleas are fragile when young and often killed when they are planted because their roots and crown are broken. Turn the plant on its side. With sharp pruning shears, cut around the bottom of the container and look to see if it is well-rooted. If it is, slip the plant out sideways by pushing from the bottom. Lower it carefully into the hole while supporting the roots with your hands. Backfill with native soil.

If the plant is not well rooted, slit the sides of the container from the bottom up in several places, then tape it back together with masking tape. Lower the plant into the hole with the taped container holding the roots in place. Loosen the tape and slide the bottom out. Slip out the cut pieces from the sides as you backfill the hole with native soil.

Press the soil down around the plant with your hands (not too hard). The top of the root ball should be even with the surrounding ground.

Make a watering basin, and water deeply right away. Then in fast-draining soils, for three days water once a day; for the next two weeks water three times a week; and for the following month water twice a week. Thereafter, for the first three years, water once a week. In clay soils you should water enough to keep the root ball damp but not soggy for the first three weeks to four weeks. Thereafter water deeply after the ground dries out.

Bougainvilleas are drought resistant not because they don't need water but because their roots go deeply into the ground until they find an underground water source. When young, they take all the water they can get, as long as drainage is adequate. Feed them once a month each year between April and August.

After three to five years you can stop fertilizing in summer, stop watering in winter, and reduce the frequency of summer watering to once a month or every six weeks — or perhaps never, depending on placement and variety. (Container-grown vines will always need regular fertilizer and water.)

Golf course superintendents often use a soil probe to determine if water is getting to the correct depth. Proper watering depth not only makes the grass healthier- it also saves water.

Since few homeowners have soil probes, the next best thing is to take a shovel and carefully cut a square plug out of your lawn. A square-bladed shovel works well for this, and makes it easier to replace the plug accurately.

The soil should be moist at the ends of the roots and slightly below them. If it is moist too deep or not deep enough, adjust your watering accordingly. Take more samples a week or so later to see if you need to make further watering adjustments.

Fertilize tropical and subtropical plants, according to their individual needs, during summer while they are growing. Continue to plant them except in interior valleys, where scorching days may burn their foliage if they are planted this late in the season. Tropicals and subtropicals give us our distinctively Southern California atmosphere, and not all are great water users, some are drought resistant.

Among the numerous tropical and subtropical plants that can deal with being planted in summer (in all but the hottest interior zones) are bougainvillea, natal plum, hibiscus, gardenia, ginger, palms, tree ferns, and many flowering trees such as golden trumpet tree (Tabebuia chrysotricha), floss silk tree (Chorisia speciosa), orchid trees (Bauhinias), crape myrtle (Lagerstroemia indica), cassias, and coral trees.

Also plant blue hibiscus (Alyogyne huegelii), a splendid dry-climate shrub from Australia with eye-catching bright blue flowers that bloom on and off year-round in full sun. It's widely available either in its natural shrub form or as a standard, with a 3 to 4 foot trunk. The only fault of blue hibiscus is that it's rangy and open, and doesn't branch freely. You can remedy this and also keep the plant blooming once a month from spring to fall if you cut back two or three of its longest branches by half or two-thirds their length.

Other choices to plant now include tropical fruit trees such as avocado, banana, citrus, pineapple guava, sapote, and cherimoya. In most areas, other than the warmest interior valleys, the early summer weather stimulates growth but isn't yet hot enough to dry them out. Keep them well watered until they become established.