The Effects of Gibberellic Acid on Plants

The gibberellins in gibberellic acid are plant hormones that stimulate plant growth. In diluted form, it's safe to use, the EPA has found, though avoid contact with eyes, never inhale it and always use gloves when handling it. More is not better when it comes to gibberellic acid. It was discovered as a result of rice plants dying from too-tall stem growth. Since the acid can have unpredictable effects, and usage varies according to the specific plant and desired result, consult your local extension agent or other knowledgeable plant authority for specific advice.

Seed Germination

Applying gibberellic acid to seeds makes them germinate quickly. The acid also pushes dormant seeds to germinate and increases successful germination of old seeds. Tubers, too, will sprout sooner if the acid is used.

Premature Flowering

If the plant is old enough, applying gibberellic acid can force early flowering. Male flowers need a less concentrated solution than female flowers. If flowering plants are given too much acid, flowering is suppressed.

Increased Fruit Yield

The application of gibberellic acid can increase fruit yield and make fruit grow more quickly. This can happen even when pollination is incomplete. In this case, the fruit will have few, if any, seeds (pollination is needed for successful seed plant reproduction).

Increased Growth

Applying gibberellic acid to trees periodically can cause them to grow throughout the season. Acid is applied near the terminal bud (a terminal bud is found at the end of a stem).

Forced Pollination

Sometimes clones that cannot reproduce by pollination between them can be forced to do so with gibberellic acid and cytokinin, another hormone that influences plant cell division. Application of the hormones also can help create hybrids between close species. The method calls for hand-pollination, with the hormones applied to the blooms.

Mitigated Frost Effect

When fruit trees in flower are hit by frost, causing the flowers to start to die, spraying gibberellic acid on the trees can help mitigate the damage.

Effect on Root Formation

When gibberellic acid is used on cuttings, the root formation might be inhibited, unaffected or promoted, depending on light and the acid concentration used, according to an experiment carried out by Jürgen Hansen of Royal Veterinary and Agricultural University, Denmark.