Landscape and Garden Checklist for May

by Sally Cunningham for Lakeside Sod/ Big Yellow Bag

May is the turning point for gardeners and homeowners. We can finally get going outside, at full throttle (mostly). Most freezing nights are past, soil is getting warmer, and leaf and flower buds are bursting. 

So… what should you do first in the flower and vegetable beds, the landscape, and the lawn?

Sally Says…

I’m proud to write a monthly column—your tips and “To Do” list—for friends and customers of the Braddell family and Lakeside Sod/ Big Yellow Bag. (The BYB is truly one of my favorite garden products that ever came on the market, since everything starts with the soil!)

What you can expect: I will suggest your steps for garden and landscape tasks, to do every month, based on three decades of hearing and answering gardeners’ questions, and knowing what tends to happen (both good and bad). I come from my own gardening experience, and my training that started as a Master Gardener at Cornell Cooperative Extension—and the rest followed. (Bio below.)

Organic gardening and IPM: I am known for writing (Rodale Books, Buffalo News) and teaching organic gardening and ecologically friendly landscaping practices, including avoidance of pesticides and synthetic fertilizers. It’s all about soil building and healthy plants that won’t be overcome by diseases and insects. So… how do my standards mesh with the lawn care experts at Lakeside Sod, who do occasionally recommend using an herbicide or other chemical? 

It’s called IPM: Integrated Pest Management. It is the pest management approach advocated by Cornell, Penn State, and most agriculture/horticulture schools. The IPM method is:

  • Maintain plant health with soil care, correct planting, watering, and maintenance.
  •  Accurately identify weeds or pests you believe to be a problem
  •  Determine your level of tolerance, patience, and how important the crop or plant is to you
  •  Choose the product that is labeled for that specific disease or insect
  •  Use the least amount that can do the job (spot-treating preferred)
  •  Use the product only at the right time (on the calendar and at the time of day)
  •  Never spray products “just in case” or thinking “it can’t hurt”. Great harm is done by applying pesticides excessively, at the wrong time, that don’t do the intended job;  they can harm human or animal health (especially pollinators) as well as the plant community in your yard.

Organic gardening or landscape is preferible, to me, and to your butterflies and birds—but IPM, with professional guidance, is the way to go if you  must address a specific problem beyond your tolerance level.

I hope you enjoy and benefit from this monthly feature.

Sally Cunningham, Horticulturist, Certified Nursery/Landscape Professional, Garden Writer

In the Flower Garden

Bulbs: It’s been a wonderful season—long-blooming daffodils especially!

  •  Do not cut back the leaves of bulb plants until they turn brown or yellow. Don’t braid the leaves either—they need sunshine to prepare for next year.
  •  Do cut back flower stems–only
  •  Sprinkle bulb-booster fertilizer around the bulb plants for future bulb growth

Perennials: Watching these leap from the soil, like miracles unfolding, is the joy of gardening!

  • Uncover perennials if you haven’t, unless you hear of a sudden, shocking freeze coming.
  • Cut back last year’s remaining sticks and old growth.
  • Watch out for the latecomers and don’t step on or dig over them (hardy begonias, balloon-flowers, some hostas)
  • Dig the weeds around them. If you have mats of impossible weeds such as goutweed, cinquefoil, horsetail, smother them with heavy cardboard, mulch, or black plastic, and watch for the weeds creeping into perennial crowns.
  • Improve the soil. Add organic fertililzer (according to directions), and top-dress the soil around the garden—perhaps an inch of Big Yellow Bag garden soil or quality compost.
  • Move, re-plant, or divide over-sized clumps (unless they are about to bloom, such as peonies, irises, or poppies).
  • If our unusually dry period continues, water plants deeply, especially if they were planted last year or prefer moist soil. 

Annuals: Professional garden center experts can tell you which basket or container plants are hardy enough for May nights below 45 degrees F.

  • Choose cold-hardy annuals, for the first hanging baskets and container plantings, such as violas and pansies.
  • Tender annuals (Impatiens, Mandevillas, Begonias, many more) do not tolerate cold nights. Many beautiful Mother’s Day baskets are tender, so if you see that temps will dip below 45 degrees F., get the plants covered or inside. 

In the Vegetable Garden

  • First fix the soil, in a flat garden or in raised beds.
  • For fertile, rich soil, just top-dress with BYB garden soil—a couple of inches, to give it a boost.
  • If the soil is compacted, infertile, or hard clay, turn lots of the garden soil into the old soil, or add quality compost
  • For flat gardens or new beds, do not pulverize the soil by over-using a tiller. The purpose of a tiller (or hand-digging) is to break up the soil surface, let in some air or rainfall, disturb young weeds, and expose some insects for the birds. Leave the soil lumpy.
  • Cool-season crops such as peas, lettuce and other leafy greens could have gone into the cool soil weeks ago—but start now anyway. Plant onions, potatoes, broccoli and cabbage (cole crops) if the soil is crumbly and draining well.
  • Hold off on warm-season plants (tomatoes, peppers, beans, squash) until the soil feels warm in your hand and nights remain above 65 degrees F. (usually around Memorial Day.)
  • Interplant herbs and flowers, and cover any bare soil with compost, straw or pine needles.
  • (My book, Great Garden Companion–at Barnes & Noble, and other bookstores–explains interplanting and companion planting options.)
  • Trees and Shrubs in the Home Landscape
  • It is a fine time to plant all woody plants—choosing carefully that your site suits the species
  • Notice how big the plant will get in the future when you buy a “cute little tree.”
  • Plant in a wide hole or bed, amended with compost or black garden soil.
  • Pruning time has passed, but corrective pruning (broken, diseased branches, or those crowding you) may be taken out.
  • Do not prune lilacs, forsythias, or other spring-flowering plants until they finish flowering, and then learn to prune. Do not flat-top shrubs with lovely, natural shapes.

Caring For Your Lawn

The lawn may be the place you (or the kids and dog) play or picnic, or it may be the frame around your landscape plants and flower gardens. The front yard may be your pride and joy, and the back yard more casual. Whatever your goals and standards, John Braddell* has the following advice: 

With the warmer weather starting earlier this spring, dandelions and broad leaf weeds are at full go. May through June is weed control time. The best IPM (Integrated Pest Management) approach is maintaining a thick, healthy lawn—with great soil so that turf grass roots can grow deeply. That healthy lawn prevents most weeks from emerging or invading. You can dig individual weeds, or use spot treatments with weed control products to completely eliminate the weeds.

Spot treating your lawn can be done with either an aerosol can or a concentrate mixed with water then applied with a pump sprayer. Broadcasting a weed and feed granular product should only be done in extreme cases when weeds have infiltrated a large majority of the lawn. Making a fertilizer application with spot weed control is the best IPM method. 

Contact the professionals at Lakeside Sod with all your lawn care needs and concerns.

*John Braddell is the founding father and now partner in Lakeside Sod, and has taught science-based lawn care to many hundreds of professionals in the turfgrass industry.