Site design and species selection should correspond to the anticipated level of maintenance a planting will receive following installation. Planting areas should be designed to provide sufficient space for personnel to maintain them. Such design considerations may include, among other things, paths within or surrounding the planting areas. The frequency of available maintenance and skill levels of those providing maintenance are important considerations that must be addressed during design.
Maintenance should include an appropriate level of watering, weeding, pruning, cultivating, and waste removal. Repair of minor washouts, mulching, soil replacement, plant replacement, and other horticultural operations may also be necessary. Planted Stormwater Management Practices will have additional unique maintenance tasks necessary to maintain their function. Any existing invasive plants that cannot be removed or outbreaks of new invasive species will have to be managed through ongoing maintenance. Selecting plants that are drought tolerant, disease resistant, competitive, and have the appropriate form at maturity will reduce maintenance needs.
Timing and frequency of maintenance tasks varies depending on the task and planting. The following are general recommendations and site- and plant-specific best practices should be followed:
- Spring clean-up typically occurs between March and May, weather dependent.
- Fertilization, if necessary, may take place between March and mid-April to spur early season growth.
- Watering is usually needed between March and November; review Watering and Irrigation for more information.
- Syringing to flush out winter salts is typically done in March.
- Pruning may be done year-round depending on the species. Follow ANSI standards to maintain intended shape and size and ensure plant health.
- DOT generally recommends cutting back perennials and grasses (species dependent) in late winter or early spring to preserve winter interest.
- Dividing and transplanting of late summer and fall blooming perennials typically occurs in May, with spring plant replacements in June.
- Dividing and transplanting of spring and early summer bulbs typically occurs in September, with fall plant replacement from September to mid-October.
- Mulching should occur from March through November as needed to replenish levels of 1 to 3 inches depending on plant type; early spring or late fall mulching is common. Mulch should be kept away from the crown of plants.
- Fall bed clean-up is typically mid-October to mid-November, weather dependent.
- Turfgrass seeding or sodding should be done between mid-March and early May or mid-August to mid-October.
- Winter maintenance is typically minimal and focused on trash removal; consider alternatives to de-icing salt where feasible.
- In general, do not work the ground if it is frozen or sodden.
Maintenance work should be performed using electric equipment to reduce associated emissions and overall embodied carbon throughout the life cycle of the project. Careful consideration of ongoing maintenance and operations can further amplify the carbon storage benefits associated with most plant material.
There are various stewardship and volunteer programs across the city that support care of landscaped areas. Some examples include: