Colorado Gardener Calendar


Find out about the latest Colorado gardening classes, events, and plant sales here. We will update this page regularly with new events or cancellations.




Harlequin's Gardens Fall Plant Sale
Tues, Aug 30-Fri, Sept 30 4795 N. 26th St, Boulder, 303-939-9403.

Rocky Mt African Violet Council Plant Sale

Sat, Sept 24

African Violet, Streptocarpus & other gesneriads. 9-1 at Tagawa Garden Center, 7711 S. Parker Rd, Centennial.

Denver Botanic Gardens Fall Plant & Bulb Sale

Fri-Sat, Sept 30-Oct1

9-5. Preview party Thurs, Sept 29, tix on sale late Aug. Plant sale tix start early Sept., 1007 York St, Denver., 720-865-3500.


Phelan Gardens TGIF with Colo Native Plant Society
Fri, Sept 16

2-4; Free. or 719-574-8058. 4955 Austin Bluffs Parkway, Colo Springs, 80918.

Corn Maze at Chatfield Farms

Fridays-Sundays, Sept 16-Oct 30

9-5; Tix available early Sept, advanced sales for members, no onsite sales. DBG Chatfield Farms, 8500 W Deer Creek Canyon Rd, Littleton.; 720-865-3500.

Colo Native Plant Society (CoNPS) 19th Annual Rare Plant Symposium

Fri, Sept 16 

8-4; $10 (precedes Annual Conference). 


CoNPS Annual Conference, "From Peaks to Prairie: Exploring Diversity & Disturbance in Front Range Ecosystems." 

Sat-Sun, Sept 17-18

Sat, 9-5; Sun field trip times vary. Sponsored by Boulder Chapter. Longmont Museum, 400 Quail Rd, Longmont. Visit for agenda & to register for activities. In-person & virtual options.

Agriculture Festival at Plains Conservation Center 

Sat, Sept 24

10-4; Celebrate food, nature & agriculture; wagon rides, 1880s homestead village & tipi camp tours, farmer's market & more. $5/vehicle. Info: 21901 E. Hampden Ave. Aurora.

Jared's Nursery 16th Annual Giant Pumpkin Weigh-off 

Sat, Sept 24

10-4; contest, food trucks, music, kids' activities, giant pumpkin drop. Free admission & parking. 10500 W Bowles Ave, Littleton. Details: 303-979-6022.

Harlequin's Gardens Holiday Gift Market 

Sat, Oct 1-Sun, Oct 30

See newsletter or for details. 4795 N 26th St., Boulder. 303-939-9403.

Nick's Garden Center Annual Giant Pumpkin Contest 

Sat, Oct 1

11-2; see for details. 2001 S Chambers Rd, Aurora. 303-696-6657.

Pumpkin Festival at Chatfield Farms 

Fri-Sat, Oct 7-9

9-4; Advanced tix sales start mid-Sept. No onsite sales. Details at; 720-865-3500. Chatfield Farms, 8500 W Deer Creek Canyon Rd, Littleton.

Fort Collins Nursery 14th Annual Giant Pumpkin Weigh-off & Fall Jamboree 

Sat, Oct 8

10-3; growers compete for awards & cash prizes. Details at; 970-482-1984; 2121 E Mulberry, Fort Collins.

Growing Gardens Community Harvest Festival 

Wed, Oct 12

4-7 pm; Free (with suggested donation of $5-10/family). Rain date Oct 19. Hawthorn Farm, 1630 Hawthorn Ave, Boulder. Info: 303-443-9952.

The Gardens on Spring Creek 3rd Annual Pumpkins on Parade 

Thurs, Oct 20-Sun, Oct 23

10-5 daily. All-ages celebration of Halloween & the harvest. $8-11, members free. 2145 Centre Ave, Fort Collins. Info:, 970-416-2486.

SEED SWAPS - People & Pollinators Action Network & Wild Ones (free admission)

Sat, 10/15/22

Denver Native Seed Swap & Giveaway, 10am -1pm, The Table Public House, 2190 S. Platte River Drive, Denver, 80223

Sat, 10/22/22

Colorado Springs Native Seed Share, 10am -1pm, Garden of the Gods Visitor Center, 1805 N 30th St, Colorado Springs, 80904

Sat, 10/29/22

Fort Collins Native Seed Swap & Giveaway, 10am -1pm, Wolverine Farm Publick House 316 Willow St, Fort Collins, 80524. Partners: PPAN, Native Plant Society of No CO, League of Women Voters Pollinator Habitat Group, Nature in the City, City of Fort Collins, Audubon of the Rockies, Wildlands Restoration, Wild Ones

More information on how to collect & clean seeds can be found here:

Cheyenne Botanic Gardens
9/24: Learning About Hops (21+). 2-3. $25. Details & Registration at 307-637-6458. 710 S. Lions Park Dr, Cheyenne, WY 82001.
CSU Extension Free Webinars
Free online classes begin at noon. 10/12: Great Plants for Fall Color. 11/9: A Gardening Year in Review.  Register at:
Colorado Native Plant Society

Ongoing May-September 

Sign up for workshops, webinars, conferences, field trips & presentations about CO native plants, habitats & gardening. See event calendar:

CO Water Garden Society
10/20: Season Wrap-up, What Worked & What Didn't. 6-7pm potluck; presentation 7pm. Freyer-Newman Center, DBG, 1007 York St, Denver. Details:
Denver Botanic Gardens 

Check for complete class listings, registration information & fees. 1007 York St, Denver.

Denver Rose Society
10/13: Roses & Semi-Shaded Spaces w/Master Rosarian Mary Kirby 8-5. 10/22: Putting Your Rose Garden to Bed. 10-noon ($30 members or $36). DBG Freyer-Newman Center, 1007 York St, Denver. Details & registration

Denver Urban Gardens 

1325 Colorado Blvd, Denver

Through Oct. 8 - Learn to Compost (Free)

Sponsored by City & Cnty of Denver & DUG, composting and vermicomposting classes. See schedule & register at DUG

Echter's Garden Center
5150 Garrison St, Arvada, CO
Free classes. 9/17: Indoor Plants 101. 10-11. Growing Great Garlic. 2-39/24 Orchids--Exotic, but Easy. 2-3. See for details & updates. 303-4214-7979.
The Gardens on Spring Creek
2145 Centre Ave, Fort Collins
Check or 970-416-2486 for class listings & fees.

Harlequin's Gardens & Sustainable Nursery

4795 N. 26th St., Boulder, 303-939-9403

9/18: Low Tech Greenhouse Design & Operation w/Mikl Brawner. 1-2:30; $20. Visit for details. Registration required. 

High Plains Environmental Center 

Check for class schedule, trail & bird walks. 970-622-9676.

Rocky Mt Seed Alliance Online Classes

Details:, 970-560-5486.

Ongoing - Seed School 101 & Grain School 101

Tagawa Gardens

7711 S. Parker Rd., Centennial; 303-690-4722.

Sign up for the newsletter to get info about classes & special events:

The Windsor Gardener (& Brewery) Classes

6461 Colorado Hwy 392, Windsor, CO

Sat, Oct 1st: Sipping with Succulents Saturday 10:30am-12pm. Join us, High Hops Brewery and The Heart Distillery for a super popular class on succulents and cactus. Then get your hands dirty and plant your very own succulent garden to take home while you sip on a select beer or cocktail. Must be 21+. Tickets: $40 at

Sat, Oct 22: Tipsy Terrariums, 10:30-12pm. Grab a drink and plant your own terrarium. Includes a glass terrarium, plants, soil, and all you need to create and care for your terrarium, plus a beer from High Hops Brewery or select cocktail from The Heart Distillery. A 21+ event.

Tickets at



2022 CSU Spur Water in the West Symposium

Wed-Thurs, Nov 2-3

Seawell Ballroom, Denver. Details at

CSU Food Systems 2022 Colorado Food Summit, Denver

Thurs, Dec 8

Subscribe to stay up-to-date at

8th Annual Landscaping with Colo Native Plants Conference

Sat, Feb 25, 2023

Keynote speaker Dr. David Inouye. Registration for this VIRTUAL Zoom event opens early Dec. 2022. Info at