Geranium in Zone 6A — Southeast

Geraniums are a classic choice for Southeast gardens, offering vibrant color and a cheerful presence throughout our long summer. Their ability to thrive in both full sun and partial shade makes them adaptable to various spots in your yard, and their continuous blooming provides a steady supply of beauty. Plus, they're relatively low-maintenance, which is always a bonus when you're dealing with the heat and humidity.

While the Southeast can present challenges like humidity and fungal disease, geraniums are surprisingly resilient when given the right care and attention. With a growing season that stretches from early April to late October, you have plenty of time to enjoy these beauties. Just be mindful of our afternoon thunderstorms and adjust your watering accordingly.

Starting geraniums from seed indoors is possible, but honestly, it's a bit of a slow process. If you're eager to get a head start, sow seeds indoors from late January through mid February, giving them about 12 weeks before transplanting. Use seed trays with a good seed-starting mix, and provide consistent warmth and bright light—a grow light works wonders, especially since our spring weather can be unpredictable.

Water gently from the bottom to avoid damping off, a common issue in our humid climate. Keep the soil consistently moist, but not soggy. Given our moderate spring, you'll need to be patient, as geraniums are known to be slow growers from seed. For the easiest results, consider purchasing established starts from a local nursery.

Once the danger of frost has passed, usually from late April through late May, it's time to transplant your geraniums outdoors. Before planting, harden off your seedlings by gradually exposing them to outdoor conditions for about a week. This helps them adjust to the sunlight, wind, and temperature fluctuations.

Plant them 10-12 inches apart in well-draining soil. Remember our clay soil tends to hold water, so amending with compost or other organic matter is crucial for good drainage. Be mindful of late frosts that can sometimes sneak in during April; keep an eye on the forecast and be prepared to cover your young plants if needed. Since they are slow from seed, most gardeners in the Southeast find that buying starts is the way to go.

Watering geraniums correctly is key to their success in the Southeast's hot, humid climate. While they need regular moisture, overwatering can quickly lead to stem rot and other fungal issues. Aim to let the top inch or two of soil dry out slightly between waterings.

During the hotter months of July and August, you may need to water every few days, especially if we're experiencing a dry spell. Check the soil moisture by sticking your finger about two inches deep; if it feels dry, it's time to water. On average, aim for about 1 inch of water per week, either from rainfall or irrigation. Water at the base of the plant to avoid wetting the foliage, which can encourage fungal diseases in our humid environment.

Signs of underwatering include wilting leaves and dry, brittle stems. Overwatering, on the other hand, can cause yellowing leaves and mushy stems. A layer of mulch around the base of the plants can help retain moisture and suppress weeds, but avoid piling it up against the stems, as this can also contribute to rot.

Pruning geraniums is a simple way to keep them looking their best and encourage continuous blooming throughout the season. The most important task is deadheading—removing spent flower clusters as soon as they start to fade. This prevents the plant from putting energy into seed production and encourages it to produce more flowers.

Simply snip off the faded flower stems just above a leaf node. You can also pinch back leggy stems to encourage bushier growth. Do this anytime during the growing season when you notice the plant becoming too stretched out. As the first frost approaches in late October, you can give your geraniums a final trim to tidy them up, but don't prune too heavily.

While you don't technically "harvest" geraniums for food, you do harvest their beauty and enjoy their continuous blooms throughout the summer. Expect your first flowers to appear from early July through late August, about 70 days after transplanting. The key is to keep deadheading faded blooms to encourage more flowers to form.

Simply remove the spent flower heads by snipping them off at the base of the stem. This not only keeps the plant looking neat but also directs its energy towards producing new blooms. As the end of the season approaches and the first frost looms in late October, you can bring your geraniums indoors to overwinter, or simply enjoy their last flush of blooms before the cold weather sets in.

Geraniums, like all plants, can encounter a few problems in the Southeast. Here are three common issues to watch out for:

Botrytis Blight

• What it looks like: Grayish-brown fuzzy mold on leaves, stems, and flowers.
• What causes it: High humidity and poor air circulation create the perfect environment for this fungal disease. Our wet-summer rainfall and humid summers make it a common problem.
• How to fix/prevent it: Improve air circulation by spacing plants properly and pruning out crowded growth. Remove and destroy infected plant parts promptly. Apply a fungicide if necessary.

Geranium Budworm

• What it looks like: Small holes in buds and flowers, often accompanied by dark droppings.
• What causes it: The larvae of moths that feed on geranium buds and flowers.
• How to fix/prevent it: Handpick caterpillars when you see them. Use Bacillus thuringiensis (Bt) spray to control infestations, especially early in the season.

Edema

• What it looks like: Small, blister-like bumps on the undersides of leaves.
• What causes it: Excessive moisture in the soil combined with cool temperatures and high humidity.
• How to fix/prevent it: Improve drainage and air circulation. Avoid overwatering, especially during cooler periods.

Southeast Specific Challenges: The hot, humid summers in the Southeast create ideal conditions for fungal diseases like botrytis blight. Regular monitoring and preventative measures, such as proper spacing and watering practices, are essential for keeping your geraniums healthy and thriving. Also, be on the lookout for Japanese beetles, which can sometimes be a nuisance, and consider deer protection if they are common in your area.

Geraniums make excellent companions for several plants in the Southeast garden. They are known to repel certain pests, making them beneficial near tomatoes, peppers, and corn. Planting geraniums near roses can also help protect them from aphids and other insects.

Avoid planting geraniums near fennel, as it can inhibit their growth. Otherwise, geraniums are generally well-behaved and get along with most other garden plants.