Borage in Zone 4A — Midwest

Borage is a fantastic addition to any Midwest garden. The cucumber-like flavor of the leaves and the beautiful star-shaped blue flowers make it a treat for both your palate and your eyes. Plus, it attracts pollinators, which is always a win for the rest of your garden during our productive, but sometimes short, summers.

Our Midwest weather can be unpredictable, but don't let that deter you. With a 128-day growing season, Borage is quick enough to mature even with our variable spring and occasional summer heat spells. Timing your planting right will have you enjoying borage all summer long.

If you're starting Borage indoors, aim to transplant seedlings outdoors in early to late May. Before planting, harden them off by gradually exposing them to outdoor conditions for about a week. This helps them adjust to the Midwest's unpredictable spring weather.

Space your Borage plants 12-18 inches apart to give them plenty of room to grow. Keep an eye on the weather forecast around transplant time, as we can still get a late frost in May. Be prepared to cover your young plants if temperatures dip unexpectedly.

Direct sowing is the preferred and easiest method for Borage in the Midwest. Sow seeds mid May through mid July, once the soil has warmed up a bit. Borage germinates best when soil temperatures are consistently around 60-70°F.

Prepare your garden bed by loosening the soil and removing any weeds. Sow seeds 1/2 inch deep and space them 12-18 inches apart. Keep the soil consistently moist until the seedlings emerge, which usually takes about a week. Borage is easy to direct sow and self-seeds readily, so be prepared for volunteers next year!

Borage needs moderate watering to thrive in our Midwest climate. While it's a fairly easy-going plant, it's not very drought-tolerant, so consistent moisture is key, especially during our occasional summer heat spells.

During the spring and early summer, when rainfall is more frequent, you might only need to supplement with watering once or twice a week, giving each plant about an inch of water. Use the "finger test" – stick your finger about 2 inches into the soil. If it feels dry, it's time to water. In the hotter, drier periods of summer, especially if we're not getting our usual wet-summer rainfall, increase watering to every other day or daily as needed.

Water at the base of the plant to avoid getting the leaves wet, as our moderate-to-humid conditions can increase the risk of fungal diseases. Signs of underwatering include wilting leaves and slow growth. Overwatering can lead to yellowing leaves and root rot, especially in our clay soil. Adding a layer of mulch around your Borage plants can help retain moisture and regulate soil temperature, which is especially helpful during summer heat spells.

You can expect your first Borage harvest in early July through late September, about 55 days after sowing. The star-shaped blue flowers are ready to harvest when they are fully open. The young leaves are also edible and taste like cucumber; harvest them when they are tender and young.

To harvest the flowers, simply snip them off with scissors or your fingers. For the leaves, gently pluck them from the plant, being careful not to damage the stems. Continuous harvesting will encourage the plant to produce more flowers and leaves throughout the season.

As we approach mid- September and the first frost, you can either let the remaining flowers go to seed for next year's crop, or harvest them and dry them for later use. Borage doesn't ripen off the vine, so make sure to harvest everything you want before the cold weather hits.

Here are some common problems you might encounter with Borage in the Midwest:

Self-Seeding Aggressively

• What it looks like: Numerous Borage seedlings popping up in unexpected places throughout your garden.
• What causes it: Borage readily self-seeds, and our fertile soil provides an ideal environment for germination.
• How to fix/prevent it: Deadhead flowers before they go to seed, or pull up unwanted seedlings as they appear. Consider growing Borage in a container to limit its spread.

Powdery Mildew

• What it looks like: White or grayish powdery coating on leaves, stems, and sometimes flowers. Leaves may curl, yellow, and die.
• What causes it: Various fungi thrive in warm days, cool nights, and moderate humidity – conditions we often experience in the Midwest. Dry leaf surfaces actually favor it.
• How to fix/prevent it: Improve air circulation by spacing plants adequately and pruning if needed. Remove affected leaves promptly. Neem oil or potassium bicarbonate sprays can help. A milk spray (1 part milk to 9 parts water) can also be effective.

Can Become Leggy

• What it looks like: Tall, spindly plants with fewer leaves and flowers, often flopping over.
• What causes it: Insufficient sunlight or overcrowding can cause Borage to become leggy.
• How to fix/prevent it: Ensure your Borage plants receive at least 6 hours of sunlight per day. Thin out plants if they are too crowded, and provide support if necessary.

Midwest Specific Challenges: Our moderate-to-hot heat and moderate-to-humid humidity during the summer can create favorable conditions for powdery mildew. The wet-summer rainfall can also contribute to fungal issues if plants are not properly spaced and ventilated.

Borage makes a great companion plant in the Midwest garden. It's known to attract pollinators, which can benefit tomatoes, squash, strawberries, and cucumbers. Borage is also thought to deter tomato hornworms, making it a valuable addition to your tomato patch. Squash and cucumbers benefit from the increased pollination. Strawberries are said to produce more fruit when planted near Borage. I have not found any bad companions to Borage.