Geranium in Zone 7A — Northeast

Geraniums are a classic choice for Northeast gardens, offering vibrant color and a cheerful look throughout our short growing season. Their versatility shines whether they're spilling out of containers, brightening up garden beds, or even attracting pollinators. Plus, their cool-night-enhanced fragrance makes them a true pleasure.

While our region presents challenges like a late start to spring and the risk of early frosts, growing geraniums successfully is absolutely achievable. With a growing season that averages around 198 days, careful timing and choosing early varieties will allow you to make the most of summer and enjoy these beauties.

Starting geraniums from seed indoors is possible, but honestly, they're slow growers, so many Northeast gardeners opt to buy established plants. If you're up for the challenge, begin in late January through mid February, giving them about 12 weeks indoors before transplanting.

Use seed trays with a good seed-starting mix, and ensure they have consistent warmth – a heat mat helps – and plenty of light, preferably from grow lights. Bottom watering is ideal to prevent damping off; simply set the tray in a shallow dish of water until the soil surface is moist. Keep in mind our late springs; don't rush them outside!

Transplant your geraniums outdoors in late April through late May, once the danger of frost has passed. Before planting, harden them off for about a week by gradually exposing them to outdoor conditions. Start with an hour or two of shade and increase the time each day.

Space them 10-12 inches apart in a sunny spot with well-drained soil. Keep an eye on the weather forecasts around transplant time; those unexpected late frosts can still sneak up on you. Honestly, for many of us in the Northeast, buying established geranium plants from a local nursery is the easiest way to guarantee a good show all summer.

Geraniums prefer moderately moist soil but don't like to be soggy, which is especially important to remember with our even rainfall. Let the top inch or two of soil dry out between waterings. Stick your finger in the soil to check – that's the best way to tell!

During the peak of summer, aim for about an inch of water per week, whether from rainfall or supplemental watering. In our moderate-to-humid climate, it's best to water at the base of the plants to avoid wetting the foliage, which can encourage fungal diseases.

Watch for drooping leaves, which can indicate either underwatering or overwatering. Yellowing leaves often mean too much water. A layer of mulch, like shredded bark, helps retain moisture and suppress weeds.

Deadheading is key to keeping your geraniums blooming all season long. Simply pinch or snip off spent flower clusters right where the stem meets the main plant.

Throughout the summer, you can also pinch back any leggy stems to encourage bushier growth and more flowers. As fall approaches and our first frost looms around late October, you can stop deadheading and let the plants focus on setting seed, though most of us just let them go and start fresh the next year.

Geraniums are grown primarily for their beautiful flowers, so "harvesting" in this context means enjoying their beauty in your garden from early July through late August. You'll know it's time when you see those first vibrant blooms appear.

The best way to "harvest" geraniums is to regularly remove faded or dead blooms. This not only keeps the plants looking tidy, but also encourages them to produce more flowers.

As our short growing season winds down and we approach the first frost in late October, there's not much to do except enjoy the last blooms. While you *could* try to overwinter them indoors, many gardeners simply compost the plants and start fresh the following spring.

Here are three common problems you might encounter with geraniums in the Northeast:

Botrytis Blight

• What it looks like: Grayish-brown mold on flowers, leaves, and stems, often starting with water-soaked spots.
• What causes it: High humidity and poor air circulation create ideal conditions for this fungal disease. Our moderate-to-humid summers can definitely contribute.
• How to fix/prevent it: Improve air circulation by spacing plants properly. Remove and destroy infected plant parts promptly. Avoid overhead watering, especially in the evening.

Geranium Budworm

• What it looks like: Small holes in buds and flowers, often with dark frass (caterpillar poop) nearby. You might see small green caterpillars hiding within the buds.
• What causes it: These caterpillars feed on the buds and flowers, causing damage and preventing blooms from opening properly.
• How to fix/prevent it: Handpick caterpillars when you see them. Insecticidal soap or Bacillus thuringiensis (Bt) can be effective if applied early in the infestation.

Edema

• What it looks like: Small, blister-like bumps on the undersides of leaves, especially during cool, cloudy weather.
• What causes it: Edema is caused by excessive water uptake when the plant is unable to transpire properly due to cool temperatures and high humidity.
• How to fix/prevent it: Improve air circulation and ensure good drainage. Avoid overwatering, especially during extended periods of cool, cloudy weather.

Northeast Specific Challenges: Our moderate heat, combined with moderate-to-humid conditions and even rainfall, means that geraniums need well-draining soil and good air circulation to prevent fungal diseases. Careful watering practices are crucial to avoid overwatering, especially during cooler spells.

Geraniums make excellent companions for several plants in a Northeast garden. They pair well with:

• Tomatoes: Geraniums are said to repel certain tomato pests, like the tomato hornworm, with their distinct scent.
• Peppers: Similar to tomatoes, geraniums can help deter pests that may attack pepper plants.
• Corn: Planted around the base of corn stalks, geraniums can act as a ground cover, suppressing weeds and helping retain moisture in our sometimes-rocky soil.
• Roses: Many gardeners believe geraniums help deter Japanese beetles, a common rose pest in our region.

Avoid planting geraniums near plants that prefer very dry conditions, as their moderate watering needs might not be compatible.