Volunteers needed for tree planting in Fairmount; 9 a.m. to 1 p.m. Free; wear sturdy shoes and clothing that can get dirty (gloves, tools provided). Rain or shine. Meet: Ward Park, 24th and Aspen Streets; 267-252-9325.

Arbor Day event with tours, arborists' demonstrations, kids' crafts, and entertainment; 9 a.m. to 6 p.m. tomorrow and Sunday. Fee: $14; $6 ages 16 to 20; $2 ages 6 to 15. Longwood Gardens, Route 1, Kennett Square; 610-388-1000;

Learn to grow beautiful roses with environmental educator Lori Hayes, 10 to 11 a.m. Free. Awbury Arboretum, Cope House, Chew Avenue; 215-849-2855.

Arbor Day celebration, with demonstrations, kids' activities; 1 to 4 p.m. Free; rain location: Clothier Memorial Hall, Scott Arboretum, (Cherry Border lawn), Swarthmore College, Route 320 and College Avenue, Swarthmore; 610-328-8025.

Delaware Center for Horticulture Rare Plant Auction Live and silent plant auctions, guest speakers. 5:30 p.m. Longwood Gardens, Route 1, Kennett Square; 302-658-6262, Ext. 100, 610-388-1000, Tickets: $200-$700; 302-658-6262, Ext. 100.

Sunday, April 29

Malvern Blooms Home and Garden Show

, with nursery, landscape and home-improvement displays, gardening seminars, crafts, music, kids' activities; 10 a.m. to 5 p.m. Free. King Street and Burke Park, Malvern;



Up ahead

Morris Arboretum classes

: Bus trip/workshop at Carolyn's Shade Garden (Bryn Mawr), May 4; fee: $24. Native tree and shrub identification, May 8, May 12 and May 19; fee: $80. Each: 10 a.m. to noon; pre-registration required; 215-247-5777, Ext. 125 or 156.

Container-gardening class, 11 a.m. to 2 p.m. May 5 (program repeats May 19) at Smith & Hawken stores: Promenade at Sagemore, 500 Route 73 South, Marlton, 856-355-3990; and Market Fair, 3535 Route 1, Princeton, 609-514-0731. Free; pre-registration required.

Garden-compost workshop and lecture, sponsored by Bucks County Master Gardeners, 7 to 9 p.m.: Levittown Library, 7311 New Falls Rd., Levittown (May 8); Milford Township Municipal Building, 2100 Krammes Rd., Spinnerstown (May 10); Neshaminy Manor Center, 1282 Almshouse Rd., Doylestown (May 14). Free (free compost bins while supply lasts); pre-registration required; 215-345-3283.

Clark Park fund-raiser to benefit park's upkeep, with cocktails, hors d'oeuvres, entertainment and live auction, 5:30 to 8 p.m. May 10 at 43d Street and Kingsessing Mall. Fee: $75; register by May 1; or 215-243-0555.

Gardening with children, program for adults, offers techniques and projects to do with children; Delaware County Master Gardeners sponsor, 10 a.m. to noon May 12. Fee: $10; preregistration required. Environmental Center, Smedley Park, 20 Paper Mill Rd., Springfield; 610-690-2655,;

Plant sales

Schuylkill Center for Environmental Education

, 8480 Hagy's Mill Rd.; 215-482-7300, Ext. 110;

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. Free; pre-registration/materials fee for some activities. Native trees, shrubs, vines, grasses, ferns and wildflowers, plus vendors, workshops, more; 8:30 a.m. to 4 p.m. tomorrow and 8:30 a.m. to 2 p.m. Sunday.

Temple University Ambler (near campus greenhouse), 580 Meetinghouse Rd., Ambler; 267-468-8400. Free. Woody plants, perennials, native plants; 9 a.m. to 3 p.m. tomorrow.

Tyler Arboretum, 515 Painter Rd., Media; 610-566-9134; Free. Trees, shrubs, perennials, annuals, herbs; 9 a.m. to 3 p.m. tomorrow.

Henry Botanic Garden, 801 Stony Ln., off Henry Lane, Gladwyne; 610-525-2037. Free. Woody plants, perennials, wildflowers, tender perennials, annuals, herbs; 9 a.m. to 4 p.m. tomorrow and Sunday.

University of Delaware Botanic Gardens, S. College Ave. (north of football stadium), behind Townsend Hall, Newark; 302-831-2531. Free. Lilacs, magnolias, unusual and difficult-to-find plants; 9:30 to 4 p.m. tomorrow.

- Jerene Schroeder