Summer-flowering hollyhocks (Alcea rosea) develop best in well-prepared flower beds with rich, evenly moist ground, so taking the time to prepare the site before planting might enhance both flowering and plant health. Although repeated in U.S. Department of Agriculture plant hardiness zones 3 through 9, hollyhocks are usually treated as biennials because older plants frequently fall victim to fungal rust. Hollyhock stems and sap can cause skin irritation, so wear gloves when planting or tending the plants.
Picking a Site
When deciding on a flower bed, pick a website that receives full, all-day sun and drains well. Avoid busy areas with poor air flow, because that can raise the odds of respiratory and rust diseases. Hollyhocks grow 5 to 6 feet tall, typically, with some varieties reaching 8 feet. Place the bed so the tall hollyhocks do not block sunlight to neighboring low-growing plants. Hollyhocks perform well when placed in front a wall or fence and their height can also supply a living display.
Soil Planning
Deep, well-drained dirt that is full of organic matter provides the very best growing conditions for hollyhocks, but they are able to survive in most soil types. Till deeply before you plant, splitting the ground to 16 inches deep. Hollyhock roots can penetrate 30 inches or deeper into the ground, so deep tilling creates a better rooting zone. Remove all weeds and their roots from the website, and any weeds growing nearby, since weeds compete with hollyhocks for moisture and nutrients and also the weeds might also harbor fungal spores.
Amending Wisely
Compost adds some nutrients and improves soil quality. Adding 2 to 4 inches of aged compost prior to planting can also improve drainage in dense dirt whilst raising the moisture-holding ability in sandy or rocky sites. Spread the compost over the lawn bed to the desired thickness before planting. Till it in to the top 12 to 16 inches of dirt and then smooth the surface of the bed with a rake. In especially hard or sandy soil, add a 6-inch layer of compost. You do not need to bring any additional fertilizer before you plant the hollyhocks.
All About Spacing
Good spacing increases air circulation and can help prevent rust issues. Spacing requirements vary depending on the expected mature size of the specific hollyhock variety, but spacing plants 18 inches apart works nicely for most types. Make the bed large enough to hold the number of hollyhocks you have planned while providing enough room to distance them 18 inches apart in all directions. After planting, cover the dirt with a 2-inch layer of mulch to keep down weeds and conserve soil moisture.