|
<br />I
<br />
<br />.~Wll~~r.~~
<br />
<br />, . " >.' '.~ ': . :.',1 .~. "'~;: ..-
<br />Step 5: Minimal Fertilization'"".. n ;.< ;.,,;A,,"
<br />I . ,,' , (".:', "F""':"':' "",';,"',";.>''',:!:.'",,
<br />Give the lawn wbatit needsbu't dOll'i overfied."
<br />For a low input lawn,:recycleclippiiigs and (irl thl'righi,
<br />season) apply commercial fertilizer at half the recom'.
<br />mended rate; avoid weed and.fe.cd formulatiori~a'nd
<br />don't. fertilize Jf rairi-i's 'immi'nent.' For a..lower;inp~t::;
<br />lawn, fertilize as above but 'Us'e encapsulated niU'oge'n,
<br />or an orgam.' c product ins.tead--'and fcrtiiizc only if soli.'
<br />tests show.; 'it' s ,needed"F9ritbe; l~l\'est )nputJai\'ii"
<br />substitute' h6rile:generated.' ';QrnposCfoc !comm"feW i'
<br />
<br />~~~:~~~,I~__~~:~~2~l~fJ~??~~t~:~f.~~~t~~;~ii;3;:~i,~1:':;.~:;.~.~.;';l~~~!
<br />
<br />How Much to Apply?
<br />
<br />The Lawn Care Field Guide lists regional resources
<br />[h~t provide recommended fertilization rates for spe-
<br />cific grass species. The ilctual amount
<br />required by a particular lawn may. how.
<br />ever, be much less than the standard
<br />recommended rate. According to the
<br />Northern Virginia Soil and Water Con-
<br />servation District a good rule of thumb
<br />iS!o use halfofwhal you think you need
<br />or half of the manufacturer's recom-
<br />mended applicmion, and never more than 44 Ibs.lacrc
<br />in a single application, This advice recognizes that
<br />grasscycling can easily provide about half the required
<br />nu[ricnrs to the lawn. It also recognizes that it is better
<br />
<br />,1"",,~...,....\,ll'BI,"\~...I~\I\;"\\,IIJI))\'''V',~
<br />
<br />Organic fertilizers that break
<br />down slowly are an excellent
<br />option for fertilization.
<br />
<br />>ld'''''''~'''''I--1..'\Nm,,:,,',"ln'Jl'''l-nl''''V/I''.l\~l'jl'I'~
<br />
<br />Table 3: General mowing heights (In inches)
<br /> Cool weather Hot Last
<br />Species and/or shade weather mow
<br />Kentucky 2.5 3.0 2.0
<br />bluegrass
<br />PerennIal 1.5 2.5 1.0
<br />ryegrass
<br />Ane 1.5 2.5 1.0
<br />fescue
<br />Buffalo- 1.5 2.5 1.0
<br />grass
<br />Tall 2.5 4.0 2,0
<br />fescue
<br />Zoysia- 0.5 1.a 0.5
<br />grass
<br />Bermuda 0.5 1.0 0.5
<br />grass
<br />Centipede 1.0 2.0 1.0
<br />grass
<br />St. Augustine 2.0 3.0 1.5
<br />grass
<br />
<br />to unJcrapply (sinl:c :Idditijlnal rCfliliz~rean always he:
<br />applicJ in the future) than 10 ove:rarrly ;lOtI risk uam-
<br />age to the gfjlSS and runoff or leaching of ~xccss
<br />nutrients. The surest way to apply Ihe right .lmount is
<br />to get <.l soil tcst, and Ihen ft:rtilizc only when the kSI
<br />indiealcs nitrogen is nccucu.
<br />
<br />J
<br />I
<br />
<br />Whefllo Apply'
<br />
<br />Table 4 indjc~te.s thc appropriate season filr fertill.
<br />zation by region and grass type. Cool season grasses
<br />ore best fertilized in the foil. when their rools orc
<br />actively growing and top growth has ceased, Warm
<br />season grasses are best fertilized in several sm~:lit dosc:s
<br />during the summer. (Summer grasses maintain root
<br />growth during wann weather,) Fertilizing in the wrong
<br />season wastes money as much of that fertilizer goes
<br />unused (and increases the risk of stream po(Jutionl.
<br />Moreover. fertilization in the wrong season can either
<br />stimulate the growth of weeds or grass growth ill the
<br />wrong time, For example, spring fertilization of cool
<br />season grasses usually gives broad leaf weeds aheadstart
<br />in competing with grass, while summer fertilization
<br />may weaken the grass and increases waler needs.
<br />
<br />I
<br />
<br />'1
<br />
<br />I
<br />
<br />I
<br />
<br />I
<br />
<br />What 10 apply?
<br />It is best to use an encapsulated formulation or an
<br />organic fertilizer rather than inorg::wic forms to mini-
<br />mize nutrient IC<lching. Encapsulated fertilizers 3re
<br />conted to release nutrients more gradually_ In leaching
<br />column tests. Alva (1992) found tho[ losses of oil three
<br />major nutrients (nitrogen, phosphorus, and potassium)
<br />were strongly reduced w.ith controlled-release fertil-
<br />izer blends. Lawn fonnulations with encapsulated nj.
<br />trogen are often labeled "WIN" for woter insoluble
<br />nitrogen.
<br />Organic fertilizers are also a good choice, as they
<br />break down more slowly than traditional chemical
<br />fertilizers. In addition, composted organ.ic fc:niHzers
<br />contain active microorganisms and humus_ Humus not
<br />only helps build soil texture. but its complex organic
<br />compounds can buffer soil. The Connecticut Agricul-
<br />lUral Experiment Station in New Haven has been
<br />comparing vegetable plots treated with compost ~\g;linst
<br />plots treated with inorg~mic ferliliz.:r. R~sults from the
<br />first 12 years ~how th<lt compost-only lr~~lment had
<br />similar yields and increased organi.: mailer :mu \vat~r
<br />retention (Long 1994). Italy's Soil lvJicfIJbiology C~n.
<br />ler found that eomposting could sharply incrc:lsc desir-
<br />able soil microorganisms (Lnng 1995.1).
<br />f)is~:lse symptoms may also be kSSt"ncd Wlll1 Of-
<br />gank fcrtilil.ers. For eX;lmplt:, rCSL":\n:hefS a[ r>,lidllgan
<br />Stale UnivCfsily found th:H hhJL~grass bwns [ft.,';\Il:J
<br />with organic fertilizL"rs suffl..'n:d less disl..';\sC [h;ln l~lWI1S
<br />(cealed willi t:hcmic.d rerliii.C\:r.s tL1)ng 1I.N5 b).
<br />
<br />I
<br />i.
<br />
<br />,
<br />
<br />I
<br />
<br />I
<br />
<br />! I
<br />
<br />I
<br />
<br />I I
<br />I I
<br />I I
<br />
<br />I
<br />I I
<br />I
<br />I
<br />I
<br />I
<br />i
<br />I
<br />I
<br />I
<br />I
<br />
<br />
<br />2GO
<br />
<br />; - ;.
<br />
<br />
<br />I
<br />
|