Borage in Zone 4B — Northeast

Borage is a fantastic addition to any Northeast garden. Its star-shaped blue flowers not only add beauty, but they also attract pollinators, which is vital for our short growing season. Plus, the cucumber-like flavor of the young leaves and flowers is a refreshing treat in summer salads, something we truly appreciate during our brief-but-productive summers.

Our zone 4B climate definitely has its quirks, with the potential for late spring frosts and the certainty of early fall frosts, making our 138-day growing season feel even shorter. But don't worry, borage is pretty forgiving, and with a little planning, you can easily enjoy a bountiful harvest.

If you're starting borage indoors, aim to transplant seedlings outdoors in late April through late May. Make sure you harden them off first by gradually exposing them to outdoor conditions for about a week. This helps them adjust to the cooler temperatures and variable weather we often see in the Northeast during that time.

Space your borage plants 12-18 inches apart. Keep an eye on the forecast for any late frosts, and be prepared to cover your young plants if needed. Those cool spring nights can be tough on tender seedlings.

Direct sowing is the easiest and most common way to grow borage, and it works great in our Northeast climate. Sow seeds outdoors in early May through mid July, once the soil has warmed up a bit. Borage isn't too picky about soil, but it does prefer well-drained soil.

Just scatter the seeds on the surface, gently press them into the soil, and keep them consistently moist until they germinate. Thin seedlings to 12-18 inches apart. Borage self-seeds readily, so be prepared to have it pop up in unexpected places next year, which can be a blessing or a curse!

Borage needs moderate watering, which is generally easy to manage in the Northeast with our even rainfall. During the spring and early summer, when rainfall is frequent, you might not need to water much at all, unless we're experiencing a particularly dry spell.

The "finger test" is your best friend: stick your finger about 2 inches into the soil. If it feels dry, it's time to water. Aim for about an inch of water per week, either from rainfall or irrigation.

Water at the base of the plant rather than overhead, especially with our moderate-to-humid summers, to help prevent fungal diseases. Signs of underwatering include wilting leaves, while overwatering can lead to yellowing leaves and root rot. A layer of mulch, like straw or wood chips, will help retain moisture and keep the soil cool during the warmer months.

You can expect your first borage harvest in early July through early October, about 55 days after sowing. The flowers are ready to harvest when they are fully open and display their vibrant blue color. The young leaves are best harvested when they are small and tender, before they become too prickly.

To harvest, simply snip off the flowers or leaves with scissors or your fingers. Regular harvesting encourages continued production, so don't be shy! As the first frost approaches in late September, harvest any remaining flowers and leaves. You can dry the flowers for later use or enjoy the leaves fresh in salads.

Here are some common problems you might encounter with borage in your Northeast garden:

Self-seeding aggressively

• What it looks like: Borage popping up everywhere in your garden, even where you didn't plant it.
• What causes it: Borage readily drops its seeds, and they germinate easily in our climate with its consistent moisture.
• How to fix/prevent it: Deadhead flowers before they go to seed, or pull up unwanted seedlings early. Consider growing borage in containers to limit its spread.

Powdery mildew

• What it looks like: White or grayish powdery coating on leaves, stems. Leaves curl, yellow, and die.
• What causes it: Fungi thrive in our warm days, cool nights, and moderate humidity. Dry leaf surfaces actually favor it.
• How to fix/prevent it: Improve air circulation by spacing plants properly. Remove affected leaves promptly. Neem oil or potassium bicarbonate sprays can help. Milk spray (1 part milk to 9 parts water) is also effective.

Can become leggy

• What it looks like: Tall, spindly plants with fewer leaves and flowers at the bottom.
• What causes it: Insufficient sunlight, especially in partial shade.
• How to fix/prevent it: Plant borage in a location that receives at least 6 hours of sunlight per day. Prune back leggy plants to encourage bushier growth.

Northeast Specific Challenges: Our moderate heat, moderate-to-humid humidity, and even rainfall can create ideal conditions for powdery mildew, so be sure to monitor your plants closely and take preventative measures.

Borage is a great companion plant for several vegetables in the Northeast garden. It attracts pollinators, which benefits tomatoes, squash, strawberries, and cucumbers. It also supposedly deters tomato hornworms. There are no significant bad companions to avoid.