After this, particularly if you have sandy soil, watch for re-emergence of the plant, as it has extremely deep roots. It may take some time to get on top of the problem. Persistence is the key. Your geraniums are being eaten by the tobacco budworm, a striped caterpillar that may be greenish, tan or reddish in color and up to three-quarters of an inch long, says UC master gardener Bill Pierce. Budworms chew round holes in foliage and burrow into buds of geraniums, petunias, calendula, penstemon and nicotiana.
Damaged buds appear dried up, fail to open or open with tattered flower petals.
Handpicking can be effective if performed on a regular basis. Bacillus thuringiensis, a natural organic product, provides good control. BT is safe for you and the environment, but one mouthful is fatal to a budworm. For best results, follow labels directions for frequency of application. Cutting edge Q. I have a Tokay grapevine I started from an old one two years ago.