Q.Jacaranda
My jacaranda is not very healthy and I can’t figure out why. I’ve had it for about a year, bought it when it was about 6′ tall. It is now approx 7-7 1/2′. The trunk is cracking at the base, the foliage is sparse, pale, with brown tips. I live in Melbourne FL. It has only flowered once. Can you please advise? Thank you.
The bark splitting could be due to environmental issues; sun scald, exposure to cold temperatures.
Check for signs of insects or disease; developing Canker can cause the trunk to split. Is the tree oozing and material?
The symptoms that the tree itself is showing can help determine a cause.
A soil test will help you determine if the plant is suffering from a nutrient deficiency, though the Jacaranda does well in poor soil. It will not tolerate clay or poor draining soil.
A poorly growing Jacaranda can benefit from a fertilizer application of a granular 12-4-8 ratio. Apply when the new growth begins to appear in spring and every 3 months until fall.
Do not over fertilizer.
Consistently moist soil is important, an established tree can withstand some dry spells.
Fertilizing late in the season can cause to rapid of growth and a trunk to split.
Research shows the the best flowering on a Jacaranda occur following a winter with temperatures above the 30's.
https://www.gardeningknowhow.com/ornamental/trees/jacaranda/jacaranda-tree-information.htm
http://plantclinic.cornell.edu/factsheets/barksplitting.pdf
https://www.gardeningknowhow.com/ornamental/trees/jacaranda/pruning-a-jacaranda-tree.htm
