Geranium in Zone 6A — Pacific Northwest

Geraniums are a classic for a reason, and they bring a lot to the table in our PNW gardens. Their vibrant colors add a splash of cheer to containers and beds, and their fragrance is a bonus. Plus, they're pretty easy to care for, and the cool nights we often have here seem to intensify their colors and fragrance.

Growing geraniums in our region does have its quirks. We have a relatively short growing season, and our springs can be cool and wet. But with a little planning and the right timing, you can definitely enjoy these beauties. Our 148-day growing season gives us plenty of time to enjoy them.

Starting geraniums from seed indoors is possible, but it can be a slow process. If you're itching to get a head start, aim to sow seeds indoors from late February through mid March, about 12 weeks before you plan to transplant them outside.

Use seed trays with a good seed-starting mix, and make sure they have plenty of warmth and light. Bottom watering can help prevent damping off, which is a common issue with seedlings. Remember, our overcast spring days mean you'll likely need supplemental lighting to get strong, healthy starts.

Since geraniums are slow to start from seed, you might find it easier to just buy starts from a local nursery. If you do start your own, harden them off for about a week before planting them out. Gradually expose them to outdoor conditions, starting with just a few hours a day.

Transplant your geraniums outdoors from late May through late June, once the danger of frost has passed. Space them about 10-12 inches apart in a sunny spot with well-draining soil. Keep an eye on the weather forecast; a late cold snap can still happen, even in late May.

Geraniums like moderate watering, but they definitely don't like soggy feet. Let the soil dry out slightly between waterings. Overwatering can lead to stem rot, which is something we definitely want to avoid in our often-damp climate.

During our mild summers, you'll likely need to water your geraniums about once a week, depending on rainfall. Stick your finger about 2 inches deep into the soil; if it feels dry, it's time to water. Aim for about an inch of water per week, either from rain or irrigation. Water at the base of the plant to avoid wetting the foliage, which can encourage fungal diseases in our climate.

Watch out for signs of underwatering, like wilting leaves, or overwatering, like yellowing leaves. A layer of mulch around your geraniums can help retain moisture and keep the soil cool, which is especially helpful during those warmer stretches.

Deadheading is key to keeping your geraniums blooming all season long. Simply pinch or snip off spent flower clusters as soon as they start to fade. This encourages the plant to put its energy into producing new blooms rather than setting seed.

Throughout the season, you can also pinch back any leggy stems to encourage a bushier growth habit. As the first frost approaches in early October, you can stop deadheading and let the plant naturally wind down.

Geraniums aren't really harvested for eating, but you can enjoy their blooms throughout the season. Expect your first flowers to appear from early August through mid September, about 70 days after transplanting.

The best way to "harvest" geraniums is to simply enjoy them as garden flowers. Regularly remove faded blooms to keep the plant looking tidy and encourage continued flowering. As the weather cools down in the fall, the flowering may slow down, but you can often still get a few blooms until the first frost hits in early October.

Here are some common problems to watch out for with geraniums in the Pacific Northwest:

Botrytis Blight

• What it looks like: Gray mold on leaves, stems, and flowers, especially in humid conditions.
• What causes it: A fungal disease that thrives in cool, wet weather. Our wet springs and occasional damp summers can create the perfect environment.
• How to fix/prevent it: Improve air circulation by spacing plants properly. Remove infected leaves and flowers promptly. Avoid overhead watering, and consider using a fungicide if the problem is severe.

Geranium Budworm

• What it looks like: Holes in buds and flowers, and small green caterpillars feeding on the plant.
• What causes it: These caterpillars are the larvae of moths. While we have fewer pest pressures than other regions, these can still show up.
• How to fix/prevent it: Handpick caterpillars off the plants. You can also use Bacillus thuringiensis (Bt), a biological insecticide, to control them.

Edema

• What it looks like: Small, blister-like bumps on the undersides of leaves.
• What causes it: This is a physiological problem caused by inconsistent watering. It's common during our wet springs when the soil stays too wet for too long.
• How to fix/prevent it: Improve drainage by amending the soil with compost. Water consistently and avoid overwatering.

Pacific Northwest Specific Challenges: Our mild heat and dry-summer rainfall can actually be beneficial for geraniums, as they tolerate heat better than many other flowers and don't like soggy conditions. However, late blight can be a concern, so be sure to monitor your plants regularly and take action if you see any signs of disease.

Geraniums are great companions for several plants in the PNW garden:

• Tomatoes, Peppers, and Corn: Geraniums are thought to repel certain pests, like tomato hornworms, that can plague these crops.
• Roses: Geraniums can help deter Japanese beetles, which can be a nuisance on roses.

Avoid planting geraniums near plants that prefer very dry conditions, as geraniums need more regular watering.