Raspberry in Zone 8B — Southeast

Raspberries are worth growing here in the Southeast. The taste of a sun-ripened raspberry, still warm from the long summer days, is hard to beat. They're incredibly versatile for jams, desserts, or just popping straight into your mouth. There's real satisfaction in harvesting your own berries.

Now, we know our hot and humid summers can bring challenges. Fungal diseases love our weather, and pests like Japanese beetles are a nuisance. But with careful timing and a little extra attention, especially during our long 255-day growing season, you can absolutely enjoy a bountiful raspberry harvest.

You'll want to get your raspberry transplants in the ground from early March through early April. This gives them time to establish before the full heat of summer hits. Before planting, be sure to harden off your transplants by gradually exposing them to outdoor conditions for about a week.

Space your raspberry plants about 2-3 feet apart to give them plenty of room to grow. Keep an eye on the weather forecast around transplant time, because we can still get some surprising temperature swings in early spring. Buying bare-root canes or potted plants in early spring or fall will give you the best start.

Raspberries need consistent moisture, especially in our hot and humid Southeast climate. Aim for about 1-2 inches of water per week, which usually works out to a deep watering a couple of times a week, depending on rainfall. You can use the "finger test" – stick your finger about 2 inches into the soil near the base of the plant. If it feels dry, it's time to water.

During our wet summers, be careful not to overwater. While raspberries need consistent moisture, they don't like sitting in soggy soil. Water at the base of the plant rather than overhead to help reduce the risk of fungal diseases, which are always a concern with our humidity. Drip irrigation works well to deliver water right where it's needed.

Signs of underwatering include wilting leaves and dry, crumbly soil. Overwatering can lead to yellowing leaves and root rot. A good layer of mulch around the base of your raspberry plants, like pine straw or wood chips, helps retain moisture and suppress weeds, but don't let it touch the canes directly.

Raspberry canes need support to keep them upright and productive. A simple two-wire trellis system works wonders. Install the trellis at planting time, or shortly after, to avoid disturbing the roots later.

Basically, you'll drive sturdy posts into the ground along your raspberry row and string two wires – one about 2-3 feet off the ground and another around 4-5 feet. As the canes grow, gently weave them between the wires to provide support. This prevents the canes from flopping over, keeps the berries off the ground, and makes harvesting much easier.

Pruning is important for maintaining healthy and productive raspberry plants. The type of pruning you'll do depends on whether you have summer-bearing or everbearing raspberries. For summer-bearing varieties, remove the canes that produced fruit immediately after harvest. These canes will not produce again.

For everbearing raspberries, you have a couple of options. You can cut all the canes down to the ground in late winter to get one large crop in the fall. Or, you can selectively prune the tips of the canes in late winter to encourage two harvests – one in summer and one in fall. As our first frost approaches around mid- November, remove any remaining unripe berries to encourage the plant to focus its energy on root development.

You can usually expect your first raspberry harvest from early May through late June here in Zone 8B. The berries are ready to pick when they are deeply colored and pull easily away from the core. A ripe berry will practically fall into your hand with a gentle tug.

Check your raspberry plants every 2-3 days during peak season, as the berries ripen quickly. Pick them in the morning after the dew has dried for the best flavor. Unlike some fruits, raspberries don't ripen off the vine, so only pick the ones that are fully ripe.

To encourage continued production, keep picking the ripe berries regularly. This signals the plant to keep producing more. As our first frost approaches around mid- November, harvest any remaining ripe berries and consider removing any new flowers to help the plant prepare for dormancy.

Here are some common problems you might encounter with raspberries in the Southeast:

Spotted Wing Drosophila

• What it looks like: Tiny flies laying eggs in ripening fruit, causing soft spots and rot.
• What causes it: These pests thrive in our humid summers.
• How to fix/prevent it: Use traps to monitor populations. Apply insecticides labeled for spotted wing drosophila if necessary, following label instructions carefully. Netting can also provide a physical barrier.

Cane Borer

• What it looks like: Wilting or dying canes with small holes bored into them.
• What causes it: Cane borers are beetles that lay eggs in the canes, and the larvae tunnel through the wood.
• How to fix/prevent it: Prune and destroy infested canes below the point of damage. Keep your raspberry patch clean and free of debris.

Gray Mold

• What it looks like: Gray, fuzzy mold on the berries, especially during wet weather.
• What causes it: This fungal disease thrives in our humid climate.
• How to fix/prevent it: Provide good air circulation by spacing plants properly and pruning. Remove and destroy infected berries promptly. Consider using a fungicide labeled for gray mold if the problem is severe.

Raspberry Crown Borer

• What it looks like: Weak, stunted canes and swellings at the base of the plant.
• What causes it: These are moth larvae that bore into the crown of the plant, damaging the root system.
• How to fix/prevent it: Difficult to control. Remove and destroy infested plants. Consider using beneficial nematodes to target the larvae in the soil.

Southeast Specific Challenges: Our hot, humid summers and wet-summer rainfall create ideal conditions for fungal diseases. Be vigilant about monitoring your plants, providing good air circulation, and using appropriate treatments when necessary. Japanese beetles can also be a problem, so be prepared to handpick them or use appropriate insecticides.

Good companion plants for raspberries include garlic, tansy, and marigolds. Garlic and tansy are thought to repel certain pests, while marigolds help deter nematodes in the soil. Planting these nearby can help protect your raspberry plants.

Avoid planting raspberries near potatoes, tomatoes, peppers, and blackberries. Potatoes, tomatoes, and peppers can harbor diseases that can also affect raspberries. Blackberries compete for nutrients and can also spread diseases. Keeping raspberries separate from these plants will help keep your patch healthy.