Shade Gardening

Shade Gardening The Good, The Bad, The Ugly 3/07

Plants Need Light to Grow Direct Sunlight Reflected or Filtered Light Shade = Muted Light, Not Absence of Light • How muted the light = degree of shade • Ever-changing • Time of day • Seasons

Types of Light Sources Best is morning! • Direct sun • Sun is lower, less intense, not blocked Midday sun is high, more intense How much sun reaches plants? • Foliage density • Branches — how distributed • Reflected only — bounces off leaves, trunks • Even petunia will not grow here! • Seasonal patterns • Full in summer — sun is high • Medium shade in spring or fall • Sun at lower angle

How Did You Get Into Shade Gardening? • Inherited it from prior resident • Put up with it — want to change • Plants grew large — shade plants below

Approaches to Shade Gardening • You have shade — doing well • If it ain’t broke, don’t fix it! • Don’t make radical changes • Don’t want to put in garden, just add some interest • Add color to foreground • Add path or other item of interest • Do spot planting • Have shady area set aside, want to do it right There is Hope!

Do YOU Appreciate Shade Gardening? • Type A — Frustrating • Doesn’t grow / bloom fast enough • Not enough to do — shade takes care of itself • Remedy: • Put garden in sunniest area • Let more light In • Type B — Suited to shade gardening • Reduced work — relaxed pace • Does not need as much maintenance • Remedy: • Increase area for shade gardening • Place for hammock!

Shade — Always Changing • Some light filters or is reflected • Amount of light — varies seasonally and daily • Landscapes change over time • Trees / shrubs grow — shade area

“Good” of Shade • Foliage doesn’t burn • Flowers you get last longer — colors more intense • Less weeds — most are “full sun” plants • Plants grow slower • Less maintenance (deadheading, etc.) • Wide plant selection — not just “bloomers” • Protects new plants until established • Less insect problems — insects more active in sun • Dead leaves under trees — winter protection

“Bad” of Shade • Plants rarely bloom — • Concentrate on form, foliage, color, texture • Less plants to choose from versus sun plants • Need to plant more densely to get quick results • Grow more slowly — take time to fill in • Plants suffer from root competition • Area under trees — messy from falling leaves, etc. • Snails / slugs • Mold / mildew • Cannot grow perfect lawn • Need to be creative to brighten dark areas

Facts of Shade Life • Branches or structures block air movement • Less weeds • Insufficient sunlight leads to leaf drop • Tree roots compete for water and nutrients • Not always caused by trees — also structures

“Ugly” of Shade = Root Competition • Robs moisture / nutrients from plants • Hard to grow in root-jammed soil • Hard to dig • Perennial weeds grow by rhizomes (not seeds) • Hard to remove (cutting causes growth) • Hand pull or dig them out • Never-ending challenge

What to Do, What to Do? • Amend soil • Try buried containers (remove bottoms or use degradable) • Dig larger-than-usual planting hole • Line with newspaper — temporarily keeps roots out • Sink pots between roots — plant in them • Water new plants heavily first summer to establish root system • Try containers above the soil • Start plants in sun to get them to bloom • Move to shade when flowering • Move back into sun when blooms begin to fade • Creeping ground covers / vines (non-invasives!) • Fewer holes to dig / fewer plants to water • Start with full-grown plants with large root balls • More digging but better, competitive roots • Remove no more than ¼ of small, secondary roots • Clean cuts — more healing — less tree damage • Keep roots intact 4 to 6 feet from trunk • Last resort, remove trees

Study Your Site — Different Times of Day — Different Times of Year • Do soil test! • Make sun map • Not sure what kind of sun you have? • Petunia test • Blooms / flourishes = full sun • Grows but does not bloom well = part sun / part shade • Struggles to grow = shade • Watch for changes. Anticipate amount of sun area will receive. • Do you have leaf drop? • Prune to allow more light / air in. • Remove lower branches (crown raising / limbing up) • NMT lower third of lower branches • Stay on ground! • Higher, use certified arborist

Right Plants — Right Light! • Choose right plants — right plant for right place! • Shade tolerant • Estimate future height / growth pattern — make shade? • Let more light in • Remove large plants casting shade • Top / trim hedges • Prune overhanging branches • Exploit reflected light — white or light surfaces • Enlarge open spaces so plants get more light • Flowering plants need 4 to 5 hours of direct light • Transplant = risky; but continuing = failure

Improve Soil • Do soil test first!! • Add organic material to hold moisture • Improve soil texture (sand, lime) • Add topsoil or manure

“ A little forethought before planting will avoid disappointments later on and go a long way to creating the effect you have in mind.” — D.A. Brown, The Shade Garden Plan Your Garden! • How does shade affect your garden? • Young trees will make more shade as they mature • How much sun will an area receive? • Consider root competition • Hard to dig up / divide plants • Consider plant spacing • Don’t grow / fill in as in sun — plant more densely • Number of plants affect on growth rate / coverage • Ground covers may not fill in completely • Plan on ⅔ plant’s mature size in shade • If light shade, use full diameter in planning • For transition areas, use plants that can take sun or shade • Plan for upcoming major changes • If older tree will be removed, don’t do major flowerbed changes underneath it.

The Fun Part - Choosing Plants! • Easy — Plant for reduced light • Hard — Plant for poor, dry soil under trees • Buy larger not smaller, cheaper plants • Plants grow slower in shade • Instant results by “head start” • Downside: Harder to dig larger holes! • Those that do well in less light • Don’t choose bloomers • Few bloom readily or heavily in shade • Occasional, seasonal bloomer okay • Match plants, shrubs, ground covers to your shade • Pick for foliage, texture, and color

The Fun Part — Choosing Plants! (cont’d.) • Replace old trees with new ones • Deep, less aggressive roots • Try evergreen foliage for off-season color • Use ground covers as filler material • Creep like carpet • Use sparingly; not as dominant feature • Vary heights, shapes, colors for interest

Time to Plant! Choices, Choices, Choices… Add to existing planting bed OR start from scratch? • Redo existing bed • Remove sod (recycle elsewhere) • Sharp shovel — cut into soil 2” — slide shovel under sod — lift off • Remove weeds / undesirables • Entire root system or will re-sprout! • Add compost, peat moss, decomposed manure, chopped leaves, organic material • Mix into top 3” — 4” of soil • If soil has clay, 6” — 8” of soil • Work together to 8” to 12” • Finish with thick mulch layer (also re-buries seeds) • Pull sprouting weeds

Pros / Cons of Redoing Existing Bed • Ineffective and impractical • Too much work — too slow • Traumatic to soil’s microorganisms • Turning soil leads to weeds sprouting (soon!) • Moves dormant seeds to surface and light • Chops up and spreads invasive rhizomes • Trees react to root cutting and soil disturbance • To them, it’s pruning • Grow many more roots within weeks • Take over bed again • Once again competes with your plants!

Fast and Easy Approach — Build New Bed on Top of Soil • Get best soil you can — Extension agent has sources • Friable • Good structure • No weeds • From open pile with organic material added, turned repeatedly so weed roots and seeds are burned off • Not in plastic bags — living soil must breathe! • Condition soil — will take several seasons • Collect, compost falling leaves

Pros and Cons of Fast and Easy Approach • No unnecessary root disturbance • Little digging! • Easy to accomplish • Like Mother Nature, layers organic material • Weed-free, root-free. • Leaves original soil intact • Old soil becomes new subsoil • Subsoil microorganisms move up to new soil • Layer (like in nature with fall leaves) • Does not destroy natural microflora • New plants grow in fresh, top-quality, weed-free soil

Steps • Day before • Mow lawn or chop back vegetation • Compost residue to enrich soil • Get soil delivered • Buy plants, put in shade, water thoroughly • The “Big Day” • Temporary weed barrier to protect new soil layer • Cover bed with 5-10 sheets of newspaper • No light — weeds die, decompose • Overlap edges, cover tears • Ink okay, no lead • Soak to prevent blowing away • Cover with 8” soil (12” if no tree roots to protect)

Plant! • Will take 18 months to establish • Just push soil aside — plant the plants • End with fairly thick mulch layer • If unable to plant right away, cover bed with mulch to keep seeds out • Stand back and enjoy!

Man-Made Shade • Inanimate objects / structures cut off sunlight • Buildings, walls, fences • Is dense shade — NO light filters through — all day • If lucky, some reflect useful light • Do petunia test! • Remedies • Plant in containers, then move them to lighter areas • Paint walls white or pale color to reflect light • If possible, remove object / structure

Designing for Shade — General Principles • Emphasize texture, form, arrangements • Keep it simple! • Design around foliage, not flowers • Use variety of evergreens • Use 1/5 of plants to retain year-round foliage • Create off-season interest in trees with colorful, unusual shapes or textures • Use subtler shades

Design Essentials Color: Use color wheel or do what pleases you • Analogous — soothing to the eye; 2 colors on each side of one color on color wheel • Complimentary — exciting; colors across from each other on color wheel; contrast so they stand out • Greens dominate — dark to lime • Dark colors — get lost in shade; surround with lighter plants • Light colors — whites, pale, silver, light pink, pale blue tone down excessive intensity and brighten

Design Essentials (cont’d.) • Variegates — stand out, create “splashes of color” • Some = less vigorous (white areas lack chlorophyll) • Don’t use too many together • Using many, separate with green foliage • Get some color from flowers • Plant in pots — move to sun to bloom — then shade

Cool and Warm Colors • Put cools in bed front; warms in back for depth • Cool: • Calm / tranquility • Makes areas seem larger • Greens and blues — things look farther away • Warm: • Stimulates eye, so gives energy • Stands out • Makes areas seem smaller and closer • Creates “sunshine” patches

Texture • More impact — glossy rather than dull leaves • More interest — use varied textures • Fine leaved — ferns • Medium leaved — astilbe • Coarse / bold leaved — large hostas • Want calm / tranquility? Use fine and medium textures • Want striking look? Use fine and bold • First, plant by spots of texture to create “effect” • Second, repeat to create sense of harmony

Form • Less likely to hold debris (leaf / needle drop) • Smaller-leaved plants • Plants with downward pointing leaves • Most likely to hold debris • Large-leaved plants • Upward pointing or horizontal leaves • Design around plant or outline of leaves • Consider growth patterns • Upright / columnar — best as shade accents • Rounded, weeping, spreading — spaciousness

Plant Selection How do deciduous forest plants respond to available light? Try to do the same! • Perennials bloom 2-3 weeks in spring • Shade tolerant plants produce foliage / blooms while sun penetrates overhead foliage, then go dormant • Select summer, fall, winter foliage for interest • Consider your personal taste • Suitable for your site? • Hardiness (we are now zone 8) • Available moisture • Soil types • Extent of shade • Resistance to pest, diseases, mildew, deer • Consider leaf shape

Understand Plant Tags • Empty circle — full sun • Half darkened circle / half light or light with cloud — partial shade • Completely darkened circle / full cloud — shade

Do You Have Wet or Dry Shade? Dry shade is most common • Hardest to garden • Root competition — take water first • Umbrella canopy on large trees with heavy foliage • Naturally dry soils (sandy, stony) — water flows through • What to do? • Don’t significantly change soil within drip line as it will damage or suffocate roots. • Remove small roots • Mix in lots of organic materials • Fertilize heavily (one for tree, one for plants) • Use organic mulch — retains moisture / prevents evaporation

Do You Have Wet or Dry Shade? (cont’d.) • Use drought resistant, shade tolerant plants • Landscape with water conservation in mind • Meet plant’s water needs, especially when freshly planted • Irrigation well • Mound 2” to 3” around plant • Fill with water — let slowly drain • After 1 year, rake soil even • Slopes • Terrace extreme slopes • Use moisture retaining soils • Keep mulch moist • Run soaker hoses parallel • Plant spreading plants at base (naturally moister)

Moist Shade — Shade Reduces Evaporation • Easier than dry shade • Constant moisture — choose plants that like it moist or wet • Better plant selection — more shade plants tolerate moisture than dry conditions • Raise bed 1′ above moist area with well-aerated topsoil • Provides constant water source! • Draw water away • If wet all year, few plants will survive – • cannot live while dormant AND wet

Turf — Why Won’t My Turf Grow? • Sun plant • Suburban trees maturing • Roots • Blocking sunlight to turf • Turf growth lags behind (less sun means less photosynthesis) • Weeds and diseases move in Still want to try? Assess your site • Shade >70% of day is hopeless! • Shadows from trees or structures • Tree shade • Root competition • Prune • Dry or wet shade?

Want to Start from Scratch? • Shade tolerant varieties • Fertile / friable soil • Rake or roll for good soil contact • Top dress — ½“ top soil or compost • Sow twice amount of recommended seed • Mulch lightly • Keep moist • Ease up when grass comes up • Use water responsibly • Comply with restrictions • Conserve water — prevent run off

Have Serviceable Lawn, Want to Improve? • Roughly rake area • Overseed with improved, shade variety at 1½ recommended rate • Keep well watered practicing conservation

Turf Maintenance (Shade Tolerant Grass Up and Established) • Moisture — need more than non-shade turf • 1½“ weekly; penetrate to minimum of 6“ • Turf competes with roots • Fertilize • Shade turf is “starved” even if fertilized • “Hungry” turf spreads slowly • Leaves bare patches • Weeds move in • Increase fertilizer rate by one-half • Follow soil test report recommendations • Cool season (Fescue, etc.) — Sept., Oct., Nov. • Warm season (Bermuda, Zoysia) — Apr., May, June.

Mow — More Blade Surface, More Ability to Make food • Let turf grow ½“ to 1“ higher than normal • Be careful! • Less blade area cut — less plant stress — roots grow and are better able to handle root competition • Keep mower blade sharp and balanced! • Cut top third of blade — cut to: • Fine fescue / rye — 2½“ • Tall fescue — 4“ • Kentucky bluegrass — 3“ • Bermuda / Zoysia — 1"

Prevent Disease • Shade turf -- an easy target • Stress of shade growing • Poor growing conditions • Most turf diseases — caused by fungi • Fungi love shade’s moisture • E.g., powdery mildew • Try: • Reducing shade • Increasing air flow • Only real solution: Remove cause of shade!

Don’t Have Shade — Need It! • Building on a sunny site • If good type trees, keep some • Create dappled shade by pruning lower branches • Tailor garden to land • Loss of shade tree (“Isabel Syndrome”) • Replace with right kind, fast growing • Shade plants with loose cover • Rapid growers can shade slower growers underneath • Success depends on local climate and season of year • South in fall, winter, spring — some time to recover • South in summer — plants will burn

Don’t Have Shade — Need It! (cont’d.) • Plant shrubs • Grow / fill in faster than trees • Less aggressive roots • Make shade but not dense • Plant vines • Plant giant or tall growing annuals • Plant tall “sun” plants to shade the “non-sun” plants • Add shade structures

Read More About Shade Gardening • Making the Most of Shade, 2005 Larry Hodgson, Rodale, Inc., USA • Taylor’s Guide to Shade Gardening, 1994, Houghton Mifflin Co., New York • Gardening in the Shade, Christopher Starbuck, Missouri Department of Agriculture, University of Missouri Extension • The Garden of Revival Expert, Dr. D.G.Hessayon, 2004, Transworld Publishers, London, Published in New York • Reader’s Digest 1001 Hints and Tips for Your Garden, 2000, The Reader’s Digest Assoc., Inc., Pleasantville, NY • Southern Living Landscape Book, 1998 and 2000, Oxmoor House, Inc., Birmingham, AL • Ortho Home Gardener’s Problem Solver, 2004, Meredith Corp., Des Moines, IA

Good, Bad, and Ugly of Shade Gardening • Described shade and light effects • Challenges and realities of shade gardening • How to garden in the shade • Working with what you have • Starting completely from scratch • Designing for shade • Dry or moist shade • Turf in shade • Don’t have shade — need it! Want a satisfying challenge? Garden in the shade! We have soil test kits!

Need more information? Call or Visit Us! www.nnmastergardeners.org Ms. Vanessa Connell Newport News Horticulture Programs Coordinator 757-591-4838 Master Gardener Helpline 757-591-4838

Hostas under deck

Japanese maple, hostas and angel wing begonias

Main garden area with hostas, astilbe, japanese anemone

Shade Gardening

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