Timing is everything when your goal is a beautiful lawn and garden. These March gardening tips and tasks apply to USDA Plant Hardiness Zones 5 and 6, which span western Pennsylvania.
Flowers and vegetables
- If you want to try growing your own plants, March is the time to start seeds of tomatoes, peppers, eggplants, and other warm-season vegetables indoors. Tomatoes should be started at the end of the month to avoid getting leggy plants in May.
- When your garden is dry enough (it feels crumbly like a chocolate cake, not mushy like Play-Doh), it’s time to grow it and get it ready for planting. Take a soil sample to your Penn State County Extension Office for analysis and work on fertilizers and other nutrients as directed.
- St. Patrick’s Day is the traditional time to plant peas and potatoes, but you may have to wait a few weeks for the soil to dry out unless you prepared the soil last fall. The rhubarb, asparagus and onion sets can also be planted now.
- Remove mulch covers from roses, azaleas, clematis vines, and other tender shrubs once night temperatures rise to 30s (be prepared to recover if a late snap arrives). However, mulch around spring flower bulbs and tender perennials as it will provide protection for emerging shoots from cold, dry winds.
- Trim winter-killed rose canes to one inch below the blackened area and all rose canes to about six inches above ground level. Trim perennials that were not cleaned last fall, as well as ornamental grasses.
Trees and shrubs
- Prune fruit trees, brambles, and grapes (except peaches and nectarines, which are best pruned before they bloom) before buds swell.
- Prune summer and fall blooming bushes now (wait to prune spring blooming bushes like azealeas until they bloom). Delay pruning evergreen shrubs and hedges until early summer.
- Spray dormant oil on trees and shrubs (except blue spruce) that are infested with scale insects or mites.
- Now is the time (before it gets too hot and dry) to plant deciduous and evergreen trees and shrubs, weather and soil conditions permitting.
- Fertilize rhododendrons, azaleas, roses, and other established ornamental trees and shrubs, as well as fruit trees. Follow the recommendations on the fertilizer bag.
Lawn care
- Fertilize your lawn with an organic or chemical fertilizer and treat the lawn, as needed, for annual crabgrass or bluegrass problems with a pre-emergent preventer (watch for air temperatures above 60 ° F for 4-5 consecutive days for the right time). Consider a product that combines the two to save application time.
- When weather conditions permit, remove excess thatch from your lawn and aerate, if necessary.
- Fertilize established lawns.
