Jacaranda trees grow in subtropical areas that experience winter low temperatures in between 35 and 40 degrees Fahrenheit. The feathery, fern-like foliage and springtime clusters of bell-shaped lavender flowers make the jacaranda a striking addition to the landscape. These trees require only minimal maintenance once established, as they thrive in most soils and garden beds.
These trees grow and flower best in sites that receive full sunlight all day. Shaded beds reduce flowering and result in weak growth. Choose planting beds that drain well, as heavy clay beds and soils that drain poorly can cause root rot and tree death. Jacaranda trees tolerate drought conditions and dry soil, so slightly sandy beds provide a good growing-location choice. Loamy soils containing compost or organic matter provide optimum drainage and help the tree remain healthy.
Over-watering can weaken jacaranda trees. The plants only require watering during the dry summer months. Deep watering every two to three weeks that supplies moisture to the top 8 to 12 inches of soil usually provides sufficient moisture for healthy plant growth. Jacaranda have a shallow root system and don't tap moisture stored deep in the ground. A light covering of mulch prevents the soil from drying too quickly, but avoid deep mulch layers, as these may retain too much moisture in the soil.
Jacaranda trees require minimal fertilization, receiving most of their nutrients from that already present in the soil. Trees grown in lawn areas typically receive enough nutrients from lawn fertilizer treatments so require no fertilizer treatments if they are growing well. Jacaranda planted in individual beds may benefit from a light application of nitrogen fertilizer each spring. The fertilizer can burn the surface roots of the tree. Applying the fertilizer to the soil surrounding the tree lets the soil and water dilute the nitrogen before it reaches the tree roots.
Pruning prevents the jacaranda tree from splitting and breaking. Trees trained to a single trunk withstand wind and adverse weather better than those allowed to grow naturally. Trimming away any branches that become larger than half the diameter of the trunk prevents breakage, as large, heavy branches may cause the trunk to split at the branch crotch. Small branches that form along the trunk and below the main canopy require removal so the jacaranda maintains its tree form.