Balsam (Impatiens balsamina) is an annual flower that grows on thick, upright stems with light green leaves that have serrated edges. The cup-shaped flowers stretch around 1 to 3 inches across. They begin blooming in the late spring and persist all the way until frost in the fall. The flowers can be solid or bicolors, and sometimes they are spotted. Balsam has a fast growth rate and should be planted in the spring after the threat of frost has passed.
|Botanical Name||Impatiens balsamina|
|Common Names||Balsam, garden balsam, rose balsam|
|Mature Size||6–30 in. tall, 6–12 in. wide|
|Sun Exposure||Full, partial|
|Soil Type||Loamy, moist, well-drained|
|Soil pH||Acidic, neutral|
|Bloom Time||Spring, summer, fall|
|Flower Color||Purple, pink, red, white, bicolors|
|Hardiness Zones||2–11 (USDA)|
Balsam plants are quite easy to grow with little required maintenance to keep them blooming all season long. They don’t have any serious issues with pests or diseases. And they generally will bounce back quickly from wilting due to hot summer temperatures and strong sunlight. When planting, adding a protective layer of mulch around the plants is ideal to keep the roots cool and retain soil moisture.
It’s recommended to pinch back the stems once the plants are around 4 inches tall to create stronger and fuller growth. Also, be aware that these flowers are quite good at self-seeding in ideal growing conditions. So be ready to pull seedlings if they spread to areas where you don’t want them. Other than that, regular watering and feeding throughout the growing season (spring to early fall) will keep your balsam flowers blooming beautifully.
These flowers grow well in both full sun and partial shade. The best growing site offers some protection from strong afternoon sun, which can cause browning of the foliage. Balsam flowers can survive in full shade, though their blooms will likely be sparse in those conditions.
Organically rich, well-draining soil is best for balsam flowers. A loamy soil is recommended, though they also can grow in sandy and clay soils. A slightly acidic to neutral soil pH is ideal, but they can handle slightly alkaline soil too.
Keep the soil of balsam plants consistently moist throughout the growing season. They can continue to bloom even during heat waves but only if they have enough to drink. Conversely, they don't tolerate drought well and will usually stop flowering if they don't get enough water. Water whenever the top inch or two of soil feels dry to the touch, but avoid overwatering and causing your plants to become waterlogged.
Temperature and Humidity
Balsam flowers do not tolerate cold temperatures (32 degrees Fahrenheit or below) well, and they are susceptible to frost. They thrive in warm temperatures, though they can wilt in summer heat waves. Moreover, due to balsam's water requirements, the plants also like some humidity. But they can tolerate drier air if their soil moisture needs are being met.
Fertilize with a balanced, slow-release flower fertilizer during the growing season, following label instructions. It also can be beneficial for healthy growth and flowering to mix some compost into the soil at the time of planting.
There are several balsam varieties, including:
- Blackberry Trifle: This plant is known for its purple and white variegated petals.
- Bush Mix: Some balsam plants can get lanky by the end of the growing season, but the Bush Mix cultivar stays compact and full.
- Tom Thumb Mix: Averaging 8 to 10 inches tall, this variety is ideal for the edge of a border or a container garden.
You probably won’t find transplants of balsam sold at a nursery, but you can easily grow this annual from seed. The seeds sprout in as little as four days in moist soil at 70 degrees Fahrenheit. Start them indoors about six to eight weeks before your area's projected last frost date, planning for about 60 days from seed to first bloom. Light hastens germination, so don’t fully cover the seeds with soil. Just gently press them into a seed-starting mix. Keep the soil consistently moist but not soggy.
When outdoor soil temperatures begin to warm (usually as the average nighttime temperatures reach about 60 degrees Fahrenheit), you can bring your balsam seedlings outdoors for progressively longer stretches. Then, once frost is no longer in the forecast, plant them in a group around a foot apart for the greatest impact.
If you want to collect seeds at the end of the season to plant in other areas, keep a baggie very close. The ripe seed heads will burst and distribute their contents everywhere when you pinch them.
Potting and Repotting Balsam
Balsam flowers can grow well in containers on balconies and terraces. Just make sure to use a large pot with ample drainage holes. The plants need at least a foot of space between one another. If you start out with a large enough container, repotting won't be necessary for these annuals.