Use & MANAGEMENT of LANDSCAPE GROUNDCOVERS

Use & MANAGEMENT OF LANDSCAPE GROUNDCOVERS

Dennis Pittenger, M.S. Area Environmental Horticulturist

University of California Cooperative Extension Los Angeles County/U.C. Riverside

• Los Angeles County/UC Riverside . Dennis Pittenger Area Environmental Horticulturist [email protected] Phone: 951.827.3320 CENTER FOR LANDSCAPE & URBAN HORTICULTURE

• B.S. & M.S. Horticulture, Ohio State University • Graduate Studies Soil in Science, UC Riverside • 34 years experience - landscape & urban horticulture – Education and applied research programs – Landscape irrigation mgt., plant water needs, weather- based irrigation control – Presentations, workshops, publications, Web .

• Los Angeles County/UC Riverside Available at: www.ucanr.edu/cluh

• Los Angeles County/UC Riverside Definition

• Trailing / spreading • Perennials • Form dense continuous soil cover • Few inches to few feet tall • Woody, succulent, herbaceous • Sometimes flowering

Functional Uses

• Unifying and Transition • Accent • Turf Substitute - less formal • Soil Stabilization • Low Maintenance Zones • Fire-wise Plant Material

Why is it all or nothing???

From: Irvine Ranch Water District Turf Removal Rebate Program

• Los Angeles County/UC Riverside “The road to hell is paved with chunky gravel and indifferently chosen plants.“ ̶ Ivette Soler. The Garden Rant Blog. Feb. 24, 2015.

Zero-scape (Not Xeriscape)

Photo: Turf Terminators From: International Business Journal 4/23/2015

• Los Angeles County/UC Riverside Selection Considerations

• Use, size, function of area – foot traffic? • Expectations for appearance • Shade or full sun • Irrigation/water requirements Use and Selection of Groundcovers

PROS CONS • Variety of plant forms, • Limited or no foot traffic textures, colors, flowers • Establishment can be slow • Low maintenance • More costly to establish • Mod. To low water req’t. than turf • Good slope cover • May harbor rodents

Establishment What • Species & sq. ft. dependent • Rooted cuttings in flats, container transplants • Sod • Hydroseed • Unrooted cuttings

Establishment When

• Fall (Sep 30-Nov 15) • Spring (Feb 15-May 1) • Reduced chances of success in other periods

Establishment How

Keep weed-free until soil is covered!!!

Establishment How 1. Kill weeds, sod, existing plants - Sod removal not required 2. No soil amendment 3. Optional: loosen/till soil 4. Wet soil pre-plant 5. Plant & water well Establishment How • Frequent irrign. 2-4 wks. • Fertilizer & Pre-emerg. herbicide w/in 1 wk. – Fertilizer/herb. combo product for turf • Gradually reduce irr. freq., increase depth • Well watered ≈1-2 yrs. Weed Management

• Keep weed-free until established and soil covered • Re-apply pre-emergent herbicide every 4-6 mos. until planting covers soil • Remove weeds regularly • Keep planting dense!!! Fertilizer Management

• 1-2 lbs. N/1,000 sq. ft. 1 yr. after planting • Then 1 lb. N/1,000 sq. ft. every 3 years (spr.-sum.) Establishment 12-14 months Water & Irrigation Management

• 40-60% of cool-season grass requirement • 40-50% ETo for acceptable performance • About 1 in. ev. 7-10 days in summer • Wet entire root zone – ≥12 in. deep www.ucanr.edu/cluh

• Los Angeles County/UC Riverside Easy Calculators for Amount

http://ucanr.edu/cluh → Landscape Water Conservation → Easy Calculators

Gallons per day or week or inches per week

Increase amounts to account for system inefficiency

Water & Irrigation Management Deficit Irrigate in Drought • Good drought resistance in woody & succulent spp. • Extend time between irrigations OR reduce applied water by 10-50% • Irrigate once every 3-6 weeks to keep alive • Wet entire root zone

Pruning & Renovating

• Edging • Size control – (non-succulent spp.) • Reinvigorate woody spp.

Pruning & Renovating • How: – Rotary mower – String/blade trimmer • Herbicide if canopy opens • When: – Just prior to growth flush – Just after flowering – Ev. 2-4 mos. keeps woody types tight Pruning & Renovating Groundcovers

Achillea tomentosa Wooly yarrow Spring

Ajuga reptans Carpet bugle Summer Baccharis pilularis Coyote bush Spring Ceanothus spp. Ceanothus Summer Cotoneaster dammeri Bearberry cotoneaster Spring Drosanthemum hispidum Pink ice plant Summer Euonymus fortunei Winter creeper Spring Hedera helix English ivy Spring

Pruning & Renovating Groundcovers

Hypericum calycinum Aaron’s beard; Spring St. Johnswort

Juniperus spp. Prostrate junipers Spring

Lantana monevidensis Trailing lantana Spring

Lonicera spp. Honeysuckle Spring

Mahonia repens Creeping mahonia Spring

Myoporum parvifolium Prostrate myoporum Summer

Osteospermum Trailing African daisy Summer fruticosum

Pruning & Renovating Groundcovers

Pachysandra terminalis Japanese spurge Spring Polygonum spp. Knotweed Spring Potentilla spp. Cinquefoil Spring Rosa spp. Creeping rose Spring Sedum spurium Stonecrop Spring Trachelospermum Star jasmine Summer jasminoides

Vinca spp. Periwinkle Summer

Lantana & Honeysuckle Star Jasmine & Red Apple Rosemary & Juniper (blue rug) Salvia & Atriplex (saltbush) Sedums & Iceplant Buffalograss Dennis Pittenger Area Environmental Horticulturist

[email protected] Phone: 951.827.3320

Center for Landscape & Urban Horticulture

• Los Angeles County/UC Riverside