September is one of the most rewarding times to be in the garden. Warm days and cool nights make it the perfect season for planting, repairing, and preparing for the months ahead. At Greenhouse Garden Center, we’re here to help with our Top 10 Gardening Tips for September, expert-led seminars, and in-depth guides on lawns, roses, garlic, and winter watering.

There is so much information available for you, we’ve done our best to pull it all together for you! The work you do now will pay off with a healthier, more beautiful garden come spring, and we’re here to help you succeed!

Contents

Top 10 Gardening Tips for September

Highlights from Our Gardening Guides

September Events at Greenhouse Garden Center

Top 10 Gardening Tips for September (Download the list here!)

1. Seed and Repair Lawns (Download our Mending Lawns Guide here!)
   September 15 is the prime date for seeding lawns. With warm soil and cool nights, your grass will establish quickly before winter. Aerate compacted areas, dethatch if needed, and reseed thin spots. Frequent light watering will keep seedbeds moist until they are established.
2. Take Advantage of Fall Planting
   Fall planting allows roots to grow strong while top growth slows. Trees, shrubs, and perennials planted now develop large root systems that support vigorous growth in spring.
3. Rest Your Roses (Download our Rose Guide here!)
   Stop fertilizing and deadheading roses by early September to help them harden off before winter. Mulch the graft point and apply copper fungicide to prevent disease.
4. Prepare for Frost (Download our Winter Watering Guide here!)
   Hard freezes can damage irrigation systems and tender plants. Drain sprinklers, protect veggies with frost cloth or cotton sheets (avoid plastic), and use black-painted water barrels filled with water to radiate warmth overnight.
5. Cover Ponds with Netting (Download our Seasonal Pond Care Guide here!)
   Falling leaves may be pretty, but they don’t belong in your pond. Prevent debris buildup and protect water quality by covering ponds with netting.
6. Plant Spring-Blooming Bulbs
   Crocus, tulips, daffodils, and hyacinths planted now will light up your spring garden. Replace older bulbs that have lost vigor, enrich the soil with compost, and experiment with naturalizing varieties for years of color.
7. Prepare Houseplants for Winter (Download our Houseplant Guide here!)
   Before moving geraniums and other plants indoors, treat them with Bonide Systemic Houseplant Insect Control to keep pests outside where they belong.
8. Plant Garlic (Download our Garlic Guide here!)
   Plant garlic now for big bulbs next summer. Choose large cloves, plant in fertile soil, mulch lightly, and water monthly through winter. Garlic thrives when it establishes roots before the ground freezes.
9. Shop for Fall Foliage (Download our Autumn Color Guide here!)
   This is the season for vibrant fall color. Planting trees and shrubs now ensures strong root growth before winter while you enjoy their seasonal beauty.
10. Add Cool-Season Color
    Brighten beds and containers with ornamental kale, cabbage, pansies, violas, mums, and asters. These hardy plants chase away the blahs and bloom even in cold weather.

Highlights from Our Gardening Guides

To help you dig deeper into fall garden care, we’ve put together expert resources:

• Mending Lawns: Learn how to aerate, dethatch, reseed, and repair thin spots for a thick, healthy lawn.
• The Rose Guide: Covers year-round rose care, pruning, pests, and fall preparation — everything from hybrid teas to hardy shrub roses.
• All About Garlic: Step-by-step instructions for planting, growing, harvesting, and storing garlic.
• Winter Watering: Why plants still need water after the first freeze, how to harden off perennials, and how to keep roots healthy through dry winters.

September Events at Greenhouse Garden Center

We’ve paired our seasonal tips with hands-on events to give you the knowledge and confidence to make your garden thrive:

• Bonsai Club with Ken | Sept. 6, 11 a.m.–12 p.m.
  Learn the art of bonsai in a friendly, hands-on club setting. Perfect for all levels. Admission is free.
• Full Moon Madness Sale | Sept. 7, All Day
  Celebrate the September full moon with one-day-only savings across the nursery.
• Fall Plantings Seminar with Rick (Everde Growers)* | Sept. 13, 10–11 a.m.
  Discover why fall is the best time to plant and how to prepare soil for long-term success.
• Fall Veggies Seminar with Brian* | Sept. 13, 11:30 a.m.–12:30 p.m.
  Learn how to extend your harvest with cool-season vegetables suited for our climate.
• Fall Garden Prep Seminar with David* | Sept. 20, 11 a.m.–12 p.m.
  Pruning, mulching, irrigating, and fertilizing — get your garden ready for winter and a spectacular spring.

*All seminars are $5 per person, with proceeds donated to local charities.

Why September Matters

As owner David Ruf puts it: “September is prime time for so many garden projects. The work you do now will pay off in a healthier, more beautiful garden come spring. Our seminars are designed to give gardeners the knowledge and confidence they need to succeed.”

So, whether you’re seeding your lawn, planting garlic, preparing your roses, or simply looking for fall color, this is the month to dig in. And with expert seminars, seasonal sales, and our helpful guides, Greenhouse Garden Center is here to make sure you succeed.

Final Reminder: September 30 is the last day to redeem your Greenhouse Garden Center reward points — don’t let them expire!