June Northern Garden Checklist

A man holding healthy, bright-red tomatoes. Nourish your garden with Milorganite fertilizer.

Flower Care:

  • Remove flowers as they fade for a neater appearance and for many plants, continual or repeat bloom.
  • Mulch gardens with a 1-2” layer of evergreen needles, shredded leaves, or other organic material to conserve moisture, moderate soil temperature and reduce weeds.
  • Protect potted plants and hanging baskets from birds, chipmunks and squirrels that often pull out, nest in or dig up these plants. Discourage them with repellents or by temporarily covering potted plants with bird netting.
  • Prune Sedum Autumn Joy and Russian sage plants that were floppy in the past. Cut 8” tall plants back halfway to encourage more compact growth.
  • Pinch mums and asters back to 6 inches throughout June for more compact growth that will be covered with flowers in fall.
  • Thin garden phlox and other overgrown perennials subject to powdery mildew and leaf spot diseases by removing one third of the stems.

Vegetable Garden Planting and Harvest:

  • Plant seeds of beans, cucumbers, corn and southern peas.
  • Once your early plantings of lettuce, radishes and beets have been harvested, add a bit of compost and Milorganite to the soil and replant the area with cucumbers, beans, onions and other summer crops.
  • Continue to plant warm season vegetables like tomatoes, peppers and melons. The warm soil and air will help get these plants off to a robust start.
  • Incorporate Milorganite, a slow-release fertilizer, into the soil of container gardens at planting. Every time you water you will be fertilizing. You won’t need to make a second application for at least 6-8 weeks.
  • Cover broccoli, cauliflower, cabbage and Brussels sprouts with a floating row covers to prevent cabbage worms from reaching and feeding on the plants. Or apply the environmentally friendly Bacillus thuringiensis kurstaki to the plant.
  • Increase your gardening space and reduce pest problems by growing pole beans, melons, squash and cucumber on a trellis, fence or decorative obelisk.

Pest and Disease Control:

  • Hand pick Japanese beetles, small, metallic-green insects, and place in container of soapy water. These voracious insects emerge in late June and feed on the flowers and leaves of over 300 different types of plants.
  • Remove spotted, blotchy or discolored leaves as soon as they are found. Sanitation is the best first step in controlling diseases.
  • Control small populations of mites and aphids with a strong blast of water from the garden hose. Larger populations can be controlled with insecticidal soap or horticulture oil. Read and follow all label directions before applications.