How To Grow Hollyhock From Seeds
Hollyhock can be grown from seeds when sown early indoors, then transplanted outside after frost; or sown directly in the garden in early summer.
Sowing Seed Indoors:
- ☑️ Sow Hollyhock seeds indoors 6-8 weeks before the last frost. In frost-free areas, sow in late winter indoors to flower the same year.
- ☑️ In a warm well-lighted area sow seeds in seed starting formula and barely cover as light aids germination.
- ☑️ Keep the soil moist at 70-75 degrees F
- ☑️ Seedlings emerge in 10-14 days
- ☑️ As soon as seedlings emerge, provide plenty of light on a sunny windowsill or grow seedlings 3-4 inches beneath fluorescent plant lights turned on 16 hours per day, off for 8 hours at night. Raise the lights as the plants grow taller. Incandescent bulbs will not work for this process because they will get too hot. Most plants require a dark period to grow, do not leave lights on for 24 hours.
- ☑️ Seedlings do not need much fertilizer, feed when they are 3-4 weeks old using a starter solution (half strength of a complete indoor houseplant food) according to manufacturer’s directions.
- ☑️ If you are growing in small cells, you may need to transplant the seedlings to 3 or 4 inch pots when seedlings have at least 2 pairs of true leaves before transplanting to the garden so they have enough room to develop strong roots
- ☑️ Before planting in the garden, seedling plants need to be “hardened off”. Accustom young plants to outdoor conditions by moving them to a sheltered place outside for a week. Be sure to protect them from wind and hot sun at first. If frost threatens at night, cover or bring containers indoors, then take them out again in the morning. This hardening off process toughens the plant’s cell structure and reduces transplant shock and scalding.
Sowing Directly in the Garden:
- ☑️ Sow the Hollyhock Seeds in a cold frame or protected seedbed in the early summer.
- ☑️ In rows 6 inches apart, just press seeds into the soil. Keep moist and protect from the sun.
- ☑️ Seedlings emerge in 12-21 days.
Planting Potted Plants in the Garden:
- ☑️ Select a location in full sun with well-drained, moist soil enriched with plenty of organic matter.
- ☑️ Prepare the bed by turning the soil under to a depth of 6-12, inches removing any debris, and lightly raking as level as possible.
- ☑️ The addition of organic matter (leaf mold, compost, well-rotted manure) benefits all gardens and is essential in recently constructed neighborhoods.
- ☑️ Plant on a cloudy day or in late afternoon to reduce transplant shock.
- ☑️ Dig a hole for each plant large enough to amply accommodate the root ball.
- ☑️ Unpot the plant and gently loosen the root ball with your hands to encourage good root growth. Be careful with hollyhocks as they have tap roots that may be easily damaged.
- ☑️ Place the top of the root ball even with the level of the surrounding soil. Fill with soil to the top of the root ball. Press soil down firmly with your hand.
- ☑️ Use the plant tag as a location marker.
- ☑️ Thoroughly water and apply a light mulch layer on top of the soil (1-2 inches) to conserve water and reduce weeds.
- ☑️ Keep weeds under control during the growing season. Weeds compete with plants for water, space and nutrients, so control them by either cultivating often or use a mulch to prevent their germination.
- ☑️ Mulches also help retain soil moisture and maintain even soil temperatures. For perennials, an organic mulch of aged bark or shredded leaves lends a natural look to the bed and will improve the soil as it breaks down in time. Always keep mulches off a plant’s stems to prevent possible rot.
- ☑️ Careful watering is essential in getting perennials off to a good start. Water thoroughly at least once a week to help new roots grow down deeply. Soil should be damp at about 1 inch below the soil surface. You can check this by sticking your finger in the soil. Water early in the morning to give all leaves enough time to dry. One inch of rain or watering per week is recommended for most perennial plants. You can check to see if you need to add water by using a rain gauge.
- ☑️ Until plants become established, some protection from extreme winds and direct, hot sunlight may be necessary. Good air movement is also important.
- ☑️ After new growth appears, a light fertilizer may be applied. Keep granular fertilizers away from the plant crown and foliage to avoid burn injury. Use low rates of a slow release fertilizer, as higher rates may encourage root rots.
- ☑️ Taller varieties may require staking to prevent them from falling over in the wind.
- ☑️ “Deadhead”, remove spent flower heads to encourage continuous flowering and prevent seed development.
- ☑️ Remove and discard foliage after a hard frost in fall.
- ☑️ In colder regions, apply another layer of mulch (1-2 inches) after the ground freezes in fall. Evergreen boughs (from Christmas trees) provide additional protection. Remove this mulch in the spring.
- ☑️ Hollyhock does not divide well as it has a tap root which is easily damaged in transplanting. To propagate allow some flowers to go to seed and move any seedlings where you want them when they are small.
- ☑️ Many gardeners do not cut back perennial flower seed heads in the fall, but wait until early spring before the new foliage appears. This provides food for wildlife over the winter.
- ☑️ Be sure to give hollyhocks plenty of air circulation as rust can be a serious disease issue otherwise.
Hollyhocks may be short lived perennials, but they often seed themselves.