Ask Mr. Smarty Plants

From another communication from you, we understand you are in a hurry to get this question resolved because you are receiving some pressure from the "Board." We are assuming this has to do with your HOA objecting in some form to your recent garden changes. Since we do not know what the disagreement involves, let us give you what we know about the changes you have made.

1. The Lady Bird Johnson Wildflower Center, home of Mr. Smarty Plants, is dedicated to the growth, propagation and protection of plants native not only to North America but to the area in which they are being grown; in your case, Palm Beach County, FL on the lower southeastern portion of the state. Begonias natively occur in subtropical and tropical moist climates, in South and Central America, Africa, and southern Asia. This means they are out of our area of expertise, and the genus Begonia does not appear in our Native Plant Database. Our further search online did not produce a Begonia 'Adorata" but there is a cultivar called 'Odorata,' we trust that is the plant in question. 

2. Since our research did not unearth any toxicity in the genus begonia, we are therefore assuming that the HOA has an objection to the treatment of the mature oak. We are not entirely clear on the arrangement of the new flower beds, but if they constitute 1-1/2 ft. of soil over a considerable portion of the oak roots, or cutting the oak roots to make room for the beds we agree there is a problem. Please read this previous Mr. Smarty Plants answer on the consequences to interfering with oak roots, including the fact that your plants may not survive the oak allelopathy anyway. Please follow the links in that answer, too, as they deal with other dangers to oak roots.

Home-owner association agreements have been held by the courts to be very tightly-binding contracts and are considered by some to be more difficult to circumvent or change than city laws and ordinances.  Oak are very valuable trees in the landscape, and protecting them should be important to the HOA. Mr. Smarty Plants is not considered an authority on interaction with HOA's, and probably our opinion has very little clout, but we do care about the plants and hope you can resolve your disagreement without the trees being damaged.