PHN BN CHO LAN

Nhiu ngi hi rng c nn dng phn chm tan hay phn ht (slow release fertilizer) cho lan hay khng?

Ngi ny ni c, ngi kia lai ni rng khng. Vy phi nghe ai? Nhiu ngi bn lan dn d khch hng b 2-3 mung phn ht vo cc chu lan mi nm 2 ln. C ngi li ni rng phn ht ch nn dng cho loi Cymbidium m thi. Nh vy ng hay hay khng ng?

Xin c nhng li tng hp v phn bn v t quyt nh.

Trn th gii c my chc ngn loi lan, mi loi mc mt ni c mt mi trng sinh sng khc nhau. Do s i hi v phn bn cho mi loi mt khc. Lan trong rng khng ai bn phn m vn ra hoa tt p, chng ta bn phn cho nc y m vn khng ra hoa. Xin nh rng lan sng ngoi thin nhin hoang d hp th nhng cht cn thit trong khng kh, hay trong nc ma, phn chim, xc cn trng v nh sng mt tri. Nhng khi chng ta mang v nui trng, mi trng sinh sng khc hn, cho nn cn phi c phn bn.

Nhng cn phi bn nh th no mi ng cch cy ra nhiu hoa m khng khi b chy r, chy l hay cht cy. Phn tch k cng trong phn bn c ti 17 cht, nhng ch c 3 cht thc l cn thit thng c vit tt l NKP, v d 10-20-30.- Nhm u: ch s ca Nitrogene (N) cn cho l v mm non cng nh thn cy lan. Nu thiu cy s cn ci, o ut, l cy vng vt khng xanh ti. Nu bn nhiu l s xanh ngt, cy s mm yu d b bnh, b gy v kh ra hoa.- Nhm th hai: ch s ca Phosphorous hay Phosphate (P) cn cho r mc mnh, ra nhiu hoa. Nu thiu cy s yu ui, mm cy v r chm pht trin v chm ra hoa v t hoa. Nu bn qu nhiu cy s ra hoa sm, cy chng gi, l s ngn li.- Nhm th ba: ch s Postassium hay Potash (K) cn cho thn r, gip cho cy hp th cht N, v vn chuyn nha cy d dng t r ti l. Nu thiu cy s khng c cng ct v t hoa, nhng nu qua nhiu, cy s cn ci, ngn ho r, u l gi s b chy.Phn bn c 2 dng chnh: tc ng nhanh (Fast release) nh phn ha tan trong nc v phn chm tan (Slow release). Loi phn ny l dng v bc c cht polymer cho nhng ht phn bn khng tan ngay trong nc, v tan ra dn dn.

Ngi ta khuyn co rng:- Nu dng phn ha tan trong nc, nn bn hng tun vi liu lng rt long ch bng hay tha c ph gt cho 4 lt nc.- Nu dng phn chm tan ch cn b 2-3 tha c ph trn mt chu rng 6 (15 cm) v mi nm 2 ln l C loi phn ni rng c hiu qu trong 9 thng nh Dynamite v 6 thng nh Osmoscote. Nhng thc t ra sao? my ngi bit r.Trong cc th phn bn thng c cht mui. Nu c nhiu mui ng li trong chu, lan s b chy r v s lm cy yu ui, ci cc v cht dn. Bn t khng sao, bn nhiu s c hi, v vy gii trng lan c kinh nghim truyn tung cu: Weekly and weakly c ngha l nn bn hng tun v bn phn long.

Dng phn chm tan c ch c li l bt i cng vic bn phn, nhng c nhiu iu bt tin l: Th phn ny cn phi trong tnh trang m t vi mt nhit ti thiu l 70F (21C) v mi lm v c v bc ngoi. Khi nhit ln cao khong 85F (29.4C) m chu li m t, v bc s v v phn bn tit ra nhiu hay t khng sao kim sot c. Vo ma Xun, khi mm cy mi mc cn phi bn phn cho r v mm cy tng trng mnh m lc ny cy cn nhiu cht Nitrogene. Nhng vo ma ny ti California v nhiu ni khc hy cn lnh cho nn phn chm tan khng v ra c. Khi tri ma lin tip vi ngy, phn bn s b nc ma tri i mt. Phn chm tan c tc dng trong 3-4 thng, nhng thng u nng phn bn mnh hn l nhng thng cui. Phn chm tan c tc dng tt vi nhng loi lc no cng cn m t nh Cymbidium, hay Miltonia nhng bt li i vi loi Dendrobium cn phi c thi gian cho cht trng ri kh ti. Khng bit chc c nh hng ca phn nhiu hay t. Khng tt vi nhng loi lan cn kh ro v khng cn phn bn trong thi gian ng ngh. Nu c tip tc bn phn, Dendrobium hay Phalaenopsis s ra cy non (Keiki) thay v ra hoa. Gi bn phn chm tan t hn l phn ha tan rt nhiu.Cu hi khc ti sao cc nh k ngh trng lan li u chung loi phn ny? Xin tha: Tit kim nhn cng. Vi nh knh v trang b ti tn h c th kim sot c nhit , m , nh sng, thi biu ti nc bn phn trong lc cy mc mnh cng nh trong thi k ngh hoc thc cho lan n theo mun. Do h bn ti a, cho cy ra nhiu, cng v vy khi chng ta mua v cy c tn li dn, l nh hng ca vic bn phn qu .

Trn thi trng hin nay c nhiu loi phn ht do nhiu hng ch to nh: Scotts, Osmocote, Schultz, Dynamite, Miracle-Gro Vy th nn mua loi no? Mu vng, mu xm hay xanh l cy? Nn nh mu sc khng cho ta bit phn ra sao, m cn phi bit r thnh phn cc hp cht trong phn bn. Th d nh: 24-4-8 hay 19-5-5 m bn cho lan ch ra ton l, kh lng c bng.

kt lun xin tm gn trong my cu: Lan cn bn phn, nhng nn bn rt t. Bn phn lm sao cho cy mc mnh v ra hoa, khng nn bn qua nhiu lm cho cy tn li.Cch y my nm mt vi hi vin hi Hoa Lan VN x dng th phn Mac Amp 10-40-6 qu lm cho cy lan tn li v cht dn. l kinh nghim qu bu cho nhng ai khng chu tm hiu thu o vn ti bn m li nghe theo nhng li mch bo v cn c.

Tm hiu vai tr ca Phn bn cho hoa Phong lan

1. Nguyn t a lng : N P K N (m) :+ Cng dng:- To thn, l, chi non, cy non, r, to lc dip t- Nu phi hp vi P s to ra Protein, gip thn cy to, mp, l chc, dy.

+ Thiu N : biu hin r phn l di gc.- Cy ci cc, l gi ban u kh u l, sau chuyn sang mu vng, r nh nh ch, mc ra ngoi nhiu nhng cn ci. Cy kh ra hoa.- u l chy kh.

P (ln) :+ Cng dng:- To r- Ra hoa- u tri- To Protein- To khng cho cy t bn trong.+ Thiu P :- Cy ci cc, l nh, c mu vng xanh m- Thn ngn, r xm en.- Khng hoc t ra hoa.+ i vi h Dendrobium : thay v ra hoa trn ngn, th n li nhy cy con.

K (Kali) :+ Cng dng:-Vn chuyn nc trong thn t gc ln ngn.+ Thiu K:- Vng hai bn mp l, gia vn cn gn mu xanh. Sau vi ngy chuyn sang mu .- Cy km pht trin, l gi vng dn 2 bn mp l. Sau chuyn sang mu .- Cy mm yu. L nhn nheo, d b su bnh tn cng.- Cy chm ra hoa, hoa nh, mu khng ti, mau tn.- Cy c hin tng mt ncTUY TA VN TI NC!

2.Nguyn t trung lng : Ca Mg S Ca (Canxi) :+ Cng dng :- Pht trin b r di, mp, r phn nhnh- Gip cy hp thu m nhanh

- Hai tun ti mt ln vo bui sng.- K P v K ( khng pha chung vi phn bn c P v K). Tt nht khng pha chung vi cc loi phn khc, ch ti mt mnh Ca- Dit ru.+ Thiu Ca :- Cy km pht trin r rt, r nh nh ch, ngn. Thn l mm yu, d b ng- Rong ru pht trin, cy khng ra hoa.

Mg ( Magi ):+ Cng dng :-Vn chuyn lng thc, thc phm, du thc vt t gc ln ngn( khc vi K ch vn chuyn nc).- L di, dy, thn mp, da dy.- To lp dip t mi.- Cn bng in t.

- Mt thng ti mt ln

+ Thiu Mg:- Cy o ut, l vng c gn xanh.- Da mng, l t ngn, mng.- Vng l, m l, l lm m en vng, vng xanh ln ln.- Mu xanh dip lc phn b khng ng u trn mt l.- t vng, thi t non, rng l t.- Hoa ra khng n c, kh n.- Cy d b su bnh

S ( lu hunh)+ Thiu S:- Ch xut hin trn t non, l non, nh (trong khi thiu N ch xut hin l gi).- Thi t non.- en, thi t non t trong gc tr ra.- L non chuyn t mu xanh sang vng trng.- L non vng nht, cy ci cc km pht trin.- S hoa trn pht hoa t.- Vin l b bm v thi.- Kch thc hoa gim.- Ho t.

Trng Lan vi phn bn th h mi

Quy trnh k thut bn phn ni chung cng nh bn phn cho lan phi tun theo nguyn tc 4 ng: ng chng loi; ng liu lng; ng thi k; ng cch.

Ty theo tui cy, theo chng loi lan v ph thuc vo nhu cu dinh dng ca tng giai on sinh trng pht trin ta xy dng ch bn phn cho lan mt cch hp l.

i vi cy ang giai on tng trng cn m bo bn phn thng xuyn (3-5 ngy cho 1 ln bn) u tin t l phn cha m (N) cao hn nhm gip cy tng sinh trng. Nu l phn NPK th ch t l 3:1:2 hoc 3:1:1 (tnh chung cho c phn bn l v phn bn gc). V d: 30-10-10; 19-6-12; HT-311= 30N-10P-10K, ORCHID-1; VTM-B1; FISH EMULSION 5-1-1 (sa c); HT-ORCHID-11 hay HP-01, HP- Hu c sinh hc; HP- Hu c khng, HT-ORCHID-12 hoc Nutricote 19-6-12.i vi cy ang giai on chun b hnh thnh hoa giai on chuyn ha rt quan trng, cn u tin bn phn ln (P) v kali (K), gim bn m (N). Cn b sung c nhng loi phn bn c cha cc nguyn t dinh dng vi lng tng cng qu trnh chuyn ha hnh thnh mm hoa.

Bn tng t l phn ln v phn kali, gim lng phn m nhm gip cho t l C/N (tch ly cht kh nhiu hn, thn l s nhanh gi hn) ca cy tng cao, thun li cho qu trnh hnh thnh mm hoa, pht trin hoa. B sung thm cc cht vi lng (c bit l vi lng B) gip lm tng cht lng ca hoa. Giai on ny cn bn nhng loi phn nh: HT-131 (10-30-10); ORCHID-2 (6-30-30); HT-ORCHID.04 (0-38-19); HT-ORCHID.05(STRONG); HT-ORCHID.09; KH2PO4; KNO3; HT-ORCHID.01 (3-6-12); Nutricote (14-14-14+ TE ).

Giai on nui v dng hoa cn cn i cc cht a lng NPK v c cc cht trung, vi lng nhm hn ch t l rng n v ko di bn ca hoa, gip cnh hoa ti mu, lu ho. Giai on ny cn kali tng cng qu trnh vn chuyn cht dinh dng t l cy vo hoa, rt cn thm t l cht m, cht calci (Ca) v vi lng gip cho hoa ti mu, ko di thi gian bo qun.

t bn ny cn u tin s dng cc dng phn c t l NPK = 1:1:1 v t l 1:1:3, c th s dng nhng loi phn bn thch hp nh: HT-113 (10-10-30) loi HT-222 (21-21-21); HT-008; Hu c vi sinh, HP- Hu c sinh hc; HP- Hu c khong. Xt khi hoa mi nh vi, xt 2 ln lin tip (mi ln cch nhau 5 ngy) vi liu 1gr/1lt nc.

Ch : i vi lan cn p dng nguyn l n t nhng n thng xuyn, u n. Da theo ma v, thi tit, da vo hng dn s dng trn nhn bao b ca tng loi phn. Tu theo tnh cht ca gi th la chn loi phn bn r cho ph hp. Nu gi th l than ci th s dng phn bn c trong ti li nh HT-11; HP-01, HP- Hu c sinh hc; HP- Hu c khong.

PHNG PHP BN PHN QUA L ( 20/05/2010 )

Phn bn l b sung thm thc n c bit l vi lng kch thch cho cy trng ra l, ra hoa nhanh hn. Phn bn l c tc dng r vi rau, cy n qu, hoa hn so vi trn la.Cy hon ton khng th pht trin bnh thng nu khng c cc nguyn t vi lng nh Bo(B), man gan(Mn), km (Zn), ng (**), Molipen(Mo), mt s cy cn c nhm (Al), silic (Si). Ngi ta chng minh nhng nguyn t ny l tuyt i cn thit cho cy. Cc nguyn t c xem nh l cc cht kch thch v cc loi phn bn cha chng c gi l cc loi phn xc tc hoc phn kch thch, chng thc y s pht trin ca thc vt. S thiu tng nguyn t vi lng v a lng ring bit trong t gy ra cc chng bnh cho thc vt, ng vt v ngi.Phng thc s dng phn bn l- S dng phn bn l phi nhng nng thch hp (theo hng dn trn bao b). Nng bn phn qua l khng c cao. Nu cao cy s b bi thc (gy c) v cht, nu bn nng thp th hiu lc khng r.- Nn phun ln b mt l c nhiu kh khng nht. Cy hp th phn bn l qua kh khng: l kh khng phn b c mt trn v mt di l. la: mt trn l mt kh khng cao hn mt di l; ng, c chua, khoai ty mt trn l mt kh khng thp hn mt di l; Nhng cy thn gs lng l kh khng ln, t 300-400, a s chng u c b tr mt di l.iu kin ngoi cnh nh hng n s ng m kh khng Tri rm kh khng m, nng gt kh khng ng; t qu kh l kh khng ng li; Gi lm kh khng ng li; Nhit : 10-30oC kh khng m, To>30oC l kh khng ng li.Thi im phun phn bn l Phun phn bn l vo lc kh khng ang m; Phun khi nhit di 30oC, tri khng nng, khng ma, khng c gi kh; phn bn l ch pht huy tc dng khi cung cp nc, phn qua r; Thi gian phun: 9-10h sng v 2-3h chiu v ma ng. 7-8h sng hoc 5-6h chiu v ma h. Phn bn l nh hng cho tng loi nh cc loi cy ly hoa, ly c, ly htphun theo hng dn ghi trn bao b; Nhng ch phm tng nng sut cy trng hon ton khng c vi ngi v cy trng v nhng cht a vo cy l nhng cht c sn trong cy trng nng thp, cha p ng cho cy pht trin tt c; khng nn dng qu liu ch nh gy c (bi thc) cho cy, nh hng ti sinh trng, pht trin.Cn ch : Khng phun khi tri ma, nng to do bay hi, t l l kh khng ng cao. Khng phun sau ma do cy no nc. Nu bm my trnh ga mnh gy nh hng c hc ln cy. C th pha ch phm vi thuc tr su bnh tit kim cng phun khi pht hin cy c su bnh (ch pha ln vo nhau nng long). Trng hp cy pht trin km c th phun ch phm nhiu ln, mi ln cch nhau 10-15 ngy.Nhng rung ch nh khng c dng ch phm Rung b su bnh khng c kh nng cu cha.. Rung thiu nc b hn nng./.

BN PHN QUA L (Phn 2) ( 07/05/2010 )Tc gi: Harmen Tjalling HOLWERDA. Ngi dch: Nguyn Vn Linh

1 L DO P DNG PHNG PHP BPQL:

Trong phn ny, nhng s kin chnh dn n tnh trng hn ch hp thu dinh dng t b r v chuyn vn chng bn trong cy c cp, v nhng gii php ngn nga v khc phc tnh trng thiu dinh dng cng s c trnh by. l cch tr li cho nhng cu hi Ti sao, Khi no th p dng BPQL.

4.1 Nhng yu t gii hn kh nng hp thu b r v chuyn vn bn trong cy:

Hin tng thiu dinh dng xy ra khi kh nng hp thu ca b r b gii hn hoc b ngn cn trong mt thi gian, do khng cung cp theo nhu cu ca cy. Nhng s kin lin quan ti vng r c th k nh sau:

a. R b tn thng: Do b bnh (tuyn trng chng hn) hoc tn thng c hc (do xi xo khi chm bn lm t r).

b. Nhng iu kin ca t khng hu ho cho b r hp thu dinh dng.

. Cht dinh dng b bt ng ho do cc vi sinh vt.. B c nh do mi trng t v cc cht hu c.. S nhim mn ( EC qu cao s gii hn kh nng hp th nc ca r cy).. S bt ng lin h ti pH (s oxy ho gy ra cho cc kim loi pH cao hoc s bt ng ca Mo pH thp).. S bt cn i dinh dng trong t (s i khng gia cc ion nh K v Ca).. Thiu oxy (t qu t).. S hot ng ca r thp (nhit thp quanh vng r trong thi k ra hoa v u tri).. Thiu nc cc cht dinh dng ngm vo (qu kh).

c. Nhu cu dinh dng nh cao: Trong sut thi k pht trin tri nhanh, nhu cu dinh dng vt qu kh nng cung cp mc d t trng rt mu m. (Brown, 1999).

d. Bn phn qua l cng c th c ch nh khi nhu cu tp trung dinh dng vo cc v tr chuyn bit bn trong cy vt qu kh nng phi tr dinh dng bn trong cy.

. iu ny thng xy ra nht trong nhng vng trng im ca cc loi tri cy ln hoc cc chm u v lin quan ti c hai s kin l nhu cu tp trung cao vo mt vng chuyn bit nhiu nguyn t trong tri cy nh N v K v h qa ca kh nng c ng thp ca cc m libe i vi mt s nguyn t no , nh Ca v B chng hn.

. Kh nng c ng cc nguyn t bn trong cy cng c th b hn ch nu hoa pht trin trc l v do dn n tnh trng hn ch s chuyn dch dinh dng trong cc m mao dn.

. Trong cc thi k hn hn hoc m khng kh cao cng c th hn ch s chuyn vn trong cc mch mao dn v ngn cn s phn phi cc dng cht bt ng bi cc m libe.

Trong cc iu kin ny khi s hp th dinh dng qua b r v chuyn dch chng bn trong cy khng th thc hin hoc b hn ch, phng php bn phn qua l c th l mt gii php.

1.2 p dng phng php BPQL:

Nhng l do chnh cho vic p dng BPQL gm c:

a. Hiu chnh hin tng thiu dinh dng: BPQL c th nhanh chng hiu chnh hin tng thiu dinh dng v phn bn c phun ngay vo ch ang thiu. Th d hin tng thiu st c th xy ra khi cy trng trn nn t st ( pH cao). Phun hp cht Fe-chelate (Fe-EDTA) c th gii quyt vn .

b. Ngn nga hin tng thiu dinh dng: Khi phn bn xung t khng pht huy c hiu qu i vi mt vi nguyn t no , th d Mn trong vng t c pH cao, p dng PBQL (vi Mn) c th ngn nga c hin tng thiu Mn.

c. Thay th hoc b sung cho phng php bn phn qua r: Vic bn phn qua l c th phn no thay th phn bn qua r nhng khng bao gi c th thay th hon ton c. BPQL gip duy tr s pht trin v mnh khe ca cy trng v lm gia tng cht lng ca nng sn v c th p dng ng lc v ng ni, hon ton c lp vi cc iu kin v t ai v nht l kh nng tc ng nhanh ca n.

S gia tng nng sut ngoi mong i sau khi p dng BPQL l do s lin hp dn n hu qa gia tng s hp thu dinh dng t b r. S gia tng ny l do vic BPQL to nn s cn bng cc cht dinh dng b thiu m li l yu t gii hn s quang hp v s sn xut sinh hc (Baier v Baierova, 1999). Nhng nh nghin cu ny th phun qua l mt lng 2.69kg N/ha v 0.96kg Mg/ha trn cy bp v thy rng kh nng hp thu gia tng theo th t l 55 kg N/ha v 6Kg Mg/ha so vi i chng.

d. Gia tng kh nng chng chu s ph hoi ca su b v bnh: iu ny d hiu v mt cy trng khe mnh th t mn cm vi cc loi su b v cc loi bnh hn.

Mt cng thc phn bn kt hp gia P v K (PK 50-30 v cht ph gia) c khm ph l c cc tc dng lm cho cy cng cp v khe mnh hn, gip cho cy trng to c kh nng chng li s ph hoi ca loi nm mc sng trn cy bng hng, cy c tm v c chua.

e. Gia tng kh nng chng li tuyt lnh: BPQL c th lm gia tng s tp trung cc mui khong vo bn trong t bo, lm h im ng ca t bo cht.

2. THI IM P DNG PHNG PHP BPQL:

BPQL ph hp, nn cn c trn nhng triu chng hin nhin c th nhn thy theo kinh nghim (nh thiu dinh dng) hoc chn on dinh dng qua l.

Cc nng gia trng cy n tri B thng ly l phn tch dinh dng hai ln mi nm:. Khi kt thc t n hoa, ly l vo thng 5 phn tch N, P, K, Ca, Mg.. Cui ma ca nhng mm u nm khi l pht trin trng thnh, ly l phn tch N, P, K Ca, Mg, Fe, Mn, Zn, **.

Hon thnh kt qu ca c hai ln phn tch v a ra quy trnh phn bn cho tng trng hp c th vo cui thng 10.

3. NHNG TNH CHT CA MT SN PHM PBQL TT:

Mt sn phm PBQL tt phi c cc c tnh sau:

6.1 Tan hon ton trong nc.6.2 tinh khit cao, khng cha cc hp cht c.6.3 Hm lng ammonia v sulphate thp.6.4 Khng cha Clor.6.5 Kh nng kt tinh dng kim cng trong ure thp di 0.35%.6.6 Cc kim loi di dng chelate.6.7 Hm lng cc gc mui thp.6.8 C th dng chung vi thuc BVTV.6.9 Nhn mc phi ghi r rng hm lng cc cht kt thnh.6.10 Hng dn s dng r rng ghi trn nhn hoc c chng trnh h tr k thut cho ngi s dng bi nh sn xut hoc n v phn phi v cc vn sau:

a. Liu lng s dng (Kg hoc lt/ha)b. S ln s dng.c. Thi k s dng trong chu k sinh trng ca cy trng.d. Nhng hn ch khi s dng (nhit cao, khng dng ban ngy, cch pha ch)e. a ch lin lc nu mun bit thm thng tin.

4. LOI PHN BN QUA L V MC S DNG:

Ni chung nhng xut v dinh dng trong vic BPQL thng theo cc thi k trong qu trnh sinh trng ca cy trng.

N:. p dng trong giai on sinh trng sinh dng gia tng hm lng N trong l cy v cc phn khc ca cy.. Ure hot ng nh mt cht kch hot. Lp cutin bao ph b mt l s phng ln sau khi ure c phun vo, iu ny lm cho cc loi PBQL khc xm nhp d dng.. Nitrate hot ng nh cht khi mo cho s hnh thnh hoa (cy xoi)P:. Hot ng nh dng cht khi u cho cy t giai on mi m, kch thch s pht trin b r khi chuyn ra trng.. S dng trc khi ra hoa cho cy m chi v ra hoa mnh m.. Trong giai on hnh thnh tri s gip cho tri cng rn v ko di thi gian trng by sau thu hoch.. p dng sau thu hoch i vi cc m hot ng bi hon dinh dng cho cy.K:. p dng trong giai on sinh trng sinh dng gia tng s cng cp ca cy.. Trong sut giai on ra hoa v hnh thnh tri s lm gia tng nhng thng s lin quan ti cht lng tri (v d: v, hm lng K, nc ct, hm lng vitamin C, hm lng cc cht rn ho tan, , nhiu acid hn, nhiu ng hn, t mn cm hn i vi cc loi bnh, v tri tt hn, mu sc p hn, kh nng chng hn cao hn, ng nht hn) v s lng (s lng nhiu hn, kch c v trng lng tri, c, ht ln hn, nng hn, gim hin tng rng tri). Qu trnh chn ca tri bt u sm hn v ko di c thi gian by bn ngoi th trng.

. p dng sau khi thu hoch vo cc m nng ng bi hon dinh dng cho cy.

Mc d c nhng ngoi l khng th b qua, nhng mc p dng di y c coi nh quy nh chung:

m c 0.5 2% ( 0.5 2kg/100 lt nc)Khi lng T 300 600 lt/ha cho rau, cc v ma trng trn ng v bng hoaT 600 800 lt/ha cho nho.T 1500 3000 lt/ha cho cy n tri.S ln s dng T 2 5 ln.Khong cch T 7 14 ngy (c th n mi thng mt ln)

5. NHNG PHT TRIN CA PHNG PHP BPQL

gia tng hiu qu ca phng php Bn phn qua l v hiu lc ca phn bn qua l, nhng thnh phn ph tr c thm vo phn bn. Nhng cht ny c th l:8.1 Cht ph ch (lm t, kt dnh, phn b u, cht ph thm )8.2 Cht kch thch v iu ho tng trng.8.3 Acid Humic.8.4 Cc amino acid.8.5 Cht kch thch sinh hc.8.6 Cht chit xut t rong bin, to.8.7 Cht thay th cc hp cht chelate (phc hp hoc hu c)8.8 Dng thc vt l (tinh th, huyn ph)

6. KT LUN.

Bn Phn Qua L, k c i vi dinh dng a lng v vi lng, l cn thit lc quan ho v nng sut, cht lng dn n gia tng li tc cho nh nng. i vi nhiu v ma khp ni trn th gii, BPQL minh chng tnh hiu qu tnh hiu lc ca n, do nng dn nn c khuyn khch p dng phng php ny k c trn cc loi cy trng cha c kho nghim ti. Ti liu ny nhm cung cp nhng quy lut chung p dng cho ng phng php BPQL i vi cc loi cy trng nh vy./

BN PHN QUA L (Phn 1) ( 07/05/2010 )Lt xem: 260Ngi trng cy ni chung v trng lan ni ring ai cng mong mun cy mnh trng c pht trin tt nht, khe mnh. S h tr t phn bn i vi cy trng l ht sc cn thit. Tuy nhin, rt nhiu ngi cha hiu ht v phn bn, dn n lm dng phn bn gy cht cy. Vnochids.net xin trn trng gii thiu cng qu v bi vit v Bn phn qua l, do ng Nguyn Vn Linh G Cty TNHH Hu C dch t bi ca tc gi Harmen Tjalling HOLWERDA.

Tc gi: Harmen Tjalling HOLWERDA.Ngi dch: Nguyn Vn Linh-

1. GII THIU:

Bn phn qua l (BPQL) c mt vai tr ngy cng gia tng trong dinh dng cy trng v c nng dn p dng t nhiu nm nay khp ni trn th gii, mc d thng tin v lnh vc ny trn cc ti liu khoa hc cn hn ch. Ch ti thi gian gn y, cc nh khoa hc mi ch tm ti v iu ny c chng kin bi hng trm chuyn gia tham d mt hi ngh quc t chuyn v BPQL.

Ti liu ny nhm minh chng s quan trng v vai tr ca BPQL i vi cc cht dinh dng a lng trong qu trnh hp thu dinh dng ca cy trng. BPQL b nhn bng cp mt hoi nghi v xem nh mt mn trang im hn l li ch thit thc trong s tng trng v pht trin ca cy trng t nng cao li tc cho nh nng. c bit i vi cc cht dinh dng a lng v cy trng cn mt lng ln trong khi l cy ch c th n nhn mt lng tng i nh so vi nhu cu. Do vic p dng BPQL cung cp cc cht dinh dng a lng trn thc t khng thng dng lm.

Cc vn thc tin ang tn ti nh ti sao, khi no v p dng cch BPQL ra sao s c trnh by trong ti liu ny.

Bn Phn Qua L l mt phng php r, d p dng v hiu qu gia tng nng sut v cht lng nng sn dn n gia tng li nhun cho nh nng nu c p dng ng cch.

S hiu bit y v BPQL s trnh c cc lm ln v s lm cho nng dn tha mn hn.

Nhng vn sau y s c gii thch theo tng phn:

. Bn phn qua l l g?

. C ch ca s hp thu v vn chuyn dinh dng.

. Ti sao x dng phng php BPQL

. Khi no th x dng phng php BPQL.

. Nhng c im ca mt sn phm PBQL tt.

. Phng php BPQL v mc p dng.

. Nhng pht trin trong cng ngh PBQL.. Kt lun.

2. BN PHN QUA L L G?

Bn phn qua l l bin php phun mt hay nhiu cht dinh dng cho cy trng ln cc phn pha trn mt t ca cy (l, cung, hoa, tri) vi mc ch nng cao s hp thu dinh dng qua cc phn trn khng ca cy trng.

3. C CH CA S HP THU V VN CHUYN CHT DINH DNG QUA B L:

hiu c chc nng ca phng php BPQL, cn gii thch r rng cc quy trnh sinh hc khc nhau ca c ch hp thu qua l v phn phi dinh dng bn trong cy trng. lm cc nhim v bn trong l hoc vn chuyn cc cht dinh dng khong ra khi l n cc b phn khc ca cy trng, mt quy trnh hp thu thng qua mng t bo (plasma membrane), t cc khng bo bn trong l (apoplast) vo bn trong t bo (symplast) s xy ra. Theo Romheld v El-Fouly, (1999) s hp thu dinh dng qua l c 5 bc nh sau:

3.1 Lm t b mt l bng dung dch phn bn:

Vch ngoi ca nhng t bo l c bao ph bi lp cutin v mt lp sp c c tnh chng thm nc rt mnh. vic hp thu cc cht dinh dng d dng, ta c th b thm cc cht ph gia (vo PBQL) lm gim sc cng b mt.

3.2 S thm nhp xuyn qua lp biu b ca vch t bo:

Khi phun phn bn qua l ln b mt ca l cy, s hp thu c th xy ra theo ba cch sau y:

a. Qua cc l nh li ti trn b mt lp ngoi b v vch t bo.b. Qua cc thy khng gia cc vch tip gip cc t bo.c. Qua kh khng gia cc t bo bo v.

Theo Eichert et al, (1998), s xm nhp ca cht lng xuyn qua b mt c sc cng cao v cc kh khng c th xy ra di mt s cc iu kin. Mt trong nhng iu kin ny l to cc git nh lin kt vi s bc hi. Khi s bc hi xy ra, mc xm nhp t cao nht v s hp thu lin tc xy ra vi phn cht rn cn li.

Nhng tc gi ny cho rng (l thuyt v) nhng gii hn vt l chng li s xm nhp qua kh khng th ng i vi cc ht git ln nhng c th khng ng i vi cc phn rn cn li v chng lin kt thnh mt lp mng trong qu trnh bc hi nc. Nhng mng mng ny thm nhp vo kh khng v khch l s trao i gia bn trong v bn ngoi l cy (Eichert and Kurkhardt, 1999).

3.3 S xm nhp cht dinh dng vo cc khng bo bn trong l cy:

Cc khng bo (apoplast) rt quan trng cha cc cht dinh dng trc khi chng c hp thu vo bn trong tng t bo. Cc cht dinh dng s vo nhng khng bo ny sau khi xm nhp t bn ngoi qua lp biu b l cng nh c hp thu t r qua cc mao mch trong thn cy.

3.3 S hp thu cht dinh dng vo bn trong t bo:

Nhng nguyn tc chung v vic hp thu cht dinh dng khong t cc khng bo vo bn trong tng t bo l cng ging nh s hp thu t r. Theo , tc hp thu nh sau:

a. Nhng phn t nh nhanh hn nhng phn t ln (urea > Fe-Chelates).b. Nhng phn t khng mang in (ni cng) nhanh hn cc ion tnh in.c. Nhng ion ho tr mt nhanh hn cc ions a ho tr (H2PO4- > HPO42-)d. pH ca khng bo (apoplast) thp s hp thu cc anions nhanh hn.e. pH ca khng bo (apoplast) cao s hp thu cc cations nhanh hn.

Kh nng hp thu ca cc t bo l cy cng b nh hng bi cc yu t ngoi vi nh m, nhit , nh sng.

C ch ty thuc nng lng hp thu dinh dng xuyn qua mng vo bn trong t bo c mi gii bi cc protein vn chuyn khc nhau nh nhng cht chuyn chc nng chuyn ti hoc cc lung tnh in vi ion H+ ATPasses. Nhng s kin ny lm gia tng lc hp thu bng cch to nn chnh ha tnh in b mt mng t bo.

S hp thu qua cc t bo l c th c iu khin qua tnh trng dinh dng ca cy, nhng y khng phi l quy lut chung mc d hin tng ny c khm ph i vi s hp thu ln. Vic hp thu ln qua l v vn chuyn xung r xy ra nhanh hn i vi cy ang thiu ln.

Bng 1: S hp thu qua l v vn hnh ca ln c theo di bng ln phng x(32P).S hp thu v vn hnh ca ln________________________________________i chng theo di(khng thiu ln) (thiu ln)Hp thu bi l x l 5.3 9.9Vn hnh ra khi l ( x l) 2.0 6.0Vn chuyn xung r 0.6 4.4Theo Clarkson v Scattergood, 1982Khi p dng nhng cht dinh dng lu ng (mobile nutrients) cho cc l non, l cn ang pht trin th s chuyn dch xung r chm hn, iu ny kch thch s hp thu dinh dng t r do b l pht trin v quang hp tt hn. i vi cc l gi, l ngng pht trin th s chuyn dch ny xy ra nhanh hn v c th ngn chn tnh trng thiu dinh dng gy ra do s hp thu khng ca b r.Cc cht dinh dng bt ng (immobile nutrients) p dng trn c l gi v l non s chuyn dch chm xung r, nh vy khng gy nn s thay i no hoc c th lm gia tng lng dinh dng hp thu t r.

3.4 S phn b cht dinh dng trong l v chuyn dch chng ra ngoi:

S phn b tng cht dinh dng ring bit bn trong v chuyn dch chng ra ngoi l sau khi phun phn bn th ty thuc vo tng m libe v tnh c ng ca h mao dn.Cc cht dinh dng lu ng libe (phloem mobile nutrients) nh N, P, K, Mg c phn b vo mi m mao dn cng nh mi m libe bn trong l cy, v mt t l ln cc cht dinh dng hp thu s c vn chuyn ra khi l ti cc b phn khc ca cy ni c nhu cu cao.

Ngc li cc cht dinh dng c kh nng c ng libe gii hn (nutrients with a restricted phloem mobility) nh Ca, **, Fe, Mn, Zn s c phn b chnh cho mi m mao dn bn trong l cy v khng c s chuyn dch ng k no ra ngoi.

Ring i vi Boron, s lu chuyn bn trong cy ty thuc rt nhiu vo cc di truyn gen v l yu t quyt nh n hiu qu ca phn bn Boron qua l.

3.6 Hiu qa ca phng php BPQL:

Theo Brown, 1999, s hiu qa ca phng php BPQL nh hng bi:

a. L v ho tnh ca phn bn s dng.

S hp thu cht dinh dng ty thuc vo cc anion ni kt. Th d s hp thu Zn(NO3)2 cao hn so vi ZnSO4 c th c gii thch bi s kt ni cation-anion (cation-anion symport).

Nm 1999, Burkhardt et al thc nghim bng cch nhng cc l Vicia faba vo dung dch 1% Zn-nitrate v dung dch 1% Zn-sulphate th thy rng khi Zn c lin kt vi gc nitrat th kh nng hp thu ln gp 3.5 ln so vi gc sulphate.Bng 2 di y c th c tham kho nh bng mu tng qut v tc hp thu bi l cy i vi cc cht dinh dng.

Cht dinh dng Thi gian l cy hp thu 50%N 1 6 giP 1 5 ngyK 10 24 giCa 1 2 ngyMg 2 5 giFe 1 ngy (8%)Mn 1 2 ngyZn 1 2 ngy

b. Kh nng xm nhp ca cht dinh dng vo bn trong t bo cht nh hng bi chng ging, loi v tui ca l cy, ho tnh ca phn bn, vo cc iu kin mi trng nh m , nhit , ngy hay m, v phng php p dng.

Phn bn cho Lan

Lan c cn phn bn hay khng? Ngi cho rng cn, ngi ni rng khng, v lan trong rng u c phn bn? Ni nh vy khng ng bi v trong rng, lan c phn chim, phn ong bm, xc cn trng, l cy mc nt c th bi dng cho cy. Hy so snh gia cy lan rng v nhng cy lan nui trng cng ngh, chng ta s c mt nhn nh r rt.

Khoa hc cho ta thy l bt c loi cy no cng cn n phn bn, nhng mi loi cn mt mc khc nhau. Nu bn ng cch, ng hm lng cy s mc nhanh, mc mnh, hoa nhiu, qu sai v c ln. Nu bn qu t, kt qu s khng c nh mun. Tri li bn qu nhiu s lm chy r v cy s cht. u l lan b chy l du hiu bn qu nhiu phn.

Sau bao nhiu nm nghin cu ngi ta bit rng tt c loi phn bn d l hu c nh phn b, phn g, phn c, v s v.v hay phn ha hc u gm 3 thnh phn theo th t N-P-K, nhng ch c phn ha hc cc nh ch to mi phn cht r rng.

PHN HA HC Cht m (Nitrogen) tt cho l v cho cy mc mnh Cht ln (Phosphorus) bn cho hoa v qu. Cht ka-li (Potassium) bn cho r hay c

Nhng cht ny thng biu tng nhiu hay t bng 3 nhm ch s. Th d:

30-10-10 tc l cht Nitrogen nhiu gp 3 ln hai cht kia gip cho l v cy mc mnh. 10-30-20 tc l trong phn c 1 phn Nitrogen, 3 phn Phophorus v 2 phn Potassium 20-20-20 tc l 3 phn u nhau.

Thiu cht m lan s mc chm, l s qut quo vng vt Thiu cht ln lan ra r t, l mu xanh tm, kh ra hoa. Thiu ca li cy khng pht trin, l vng a.

Kinh nghim cho bit rng: Nhng cy ngoi nh nng cn nhiu phn hn nhng cy mc trong bng mt. Ch nn pha vi hay theo ch dn ca nh sn xut. Cy nguyn ging (species) cn t phn hn nhng cy lai ging (hybrids). Bn t phn cy khng cht, tri li bn nhiu phn c th lm cht cy. Nn bn vi dung lng thp tc l ch hay li ch dn v bn hng tun (Fertilize weakly and weekly) Nn dng nhng th phn c th ha tan trong nc m khng ng cn. Khng nn dng phn c cht Urea v phi cn mt thi gian mi c tc dng. Khng nn dng phn vin, phn que hay phn ht c th lm chy r Khng nn dng phn chm tan (slow released) v phi trn 70F hay 21C mi tan a lan (Terrestrial) cn nhiu phn bn hn phong lan (Epiphyte) Khng nn dng phn bn cho c hay cc cy ci khc ti cho lan, v nhng loi phn ny rt mnh. Th d 30-10-10 mnh gp 10 ln 3-1-1. Khng nn bn phn khi r cy qu kh, tt nht l ti nc ngy hm trc, hm sau s bn phn. Cy s khng b st v phn d thm vo trong chu.

PHN HU CNhng th phn ny khng c ph thng bi v t c ngi ch to, ngoi tr nc c (fish emulsion) c ch s 3-1-1. Cc th phn kh ph bin nh phn b phn, phn g, bnh du v.v cn phi cho mc sau pha vi nc v ti. Nhng nhng th ny khng c phn cht r rng hn na li c mi v c th c nhiu vi trng hay nm bnh trong .

Mt ng ch tim may ni l, khi cn ng Phan nh Phng, Saigon, ng ngm u tm xng c trn sn thng, my thng sau dng ti cho lan cy ln mnh v cho nhiu hoa. ng tic rng khng th thc hnh ti y v hng xm phn nn v mi hi nng nc.

Mt s hi vin cc Hi Hoa Lan Hoa K min Nam California, theo li khuyn co ca mt din gi khuyn l nn dng phn b bn cho cy lan Hc nh Phaius tankervillae. Hi cch bn ra sao? ng ta ni: c vic ly phn b lt vo y chu ri trng lan ln trn. Bo hi 80-90% cy b thi r v cht. Cch tt hn c l ngm phn trong nc khong 2-3 tun l ri pha long vi nc ti cho lan, nhng phi chu ngi mi phn b trong 2-3 ngy.

Ngay c phn c, d 2-3 nm vn cn mi hi thi d d nhng n rui nhng u ko n. Vn khc l nhng cy yu ui thng b vi trng c sn trong phn hu c d dng xm nhp v ly lan n nhng cy khc.

Thc t cho chng ta bit phn hu c kh tt cho lan v cc th phn ny khng qu mnh, nhng cch bin ch khng r rt phi ty theo kinh nghim li thm nng mi v khng bo m v v sinh cho cy ci.

Phn ha hc cng khng qu t m li c phn cht r rng, bo m cho hiu qu. Ngi ta cng khuyn rng khng nn dng mt thng hiu m nn thay i, nhng khng thy ai ni r l ti sao.

Mong rng nhng kinh nghim k trn s gip chng ta c nhng cy lan khe mnh v nhiu hoa.

Nn dng phn chm tan hay khng?

Nhiu ngi hi rng c nn dng phn chm tan hay phn ht (slow release fertilizer) cho lan hay khng?

Ngi ny ni c, ngi kia lai ni rng khng. Vy phi nghe ai? Nhiu ngi bn lan dn d khch hng b 2-3 mung phn ht vo cc chu lan mi nm 2 ln. C ngi li ni rng phn ht ch nn dng cho loi Cymbidium m thi. Nh vy ng hay hay khng ng?

Xin c nhng li tng hp v phn bn v t quyt nh.

Trn th gii c my chc ngn loi lan, mi loi mc mt ni c mt mi trng sinh sng khc nhau. Do s i hi v phn bn cho mi loi mt khc. Lan trong rng khng ai bn phn m vn ra hoa tt p, chng ta bn phn cho nc y m vn khng ra hoa. Xin nh rng lan sng ngoi thin nhin hoang d hp th nhng cht cn thit trong khng kh, hay trong nc ma, phn chim, xc cn trng v nh sng mt tri. Nhng khi chng ta mang v nui trng, mi trng sinh sng khc hn, cho nn cn phi c phn bn.

Nhng cn phi bn nh th no mi ng cch cy ra nhiu hoa m khng khi b chy r, chy l hay cht cy. Phn tch k cng trong phn bn c ti 17 cht, nhng ch c 3 cht thc l cn thit thng c vit tt l NKP, v d 10-20-30.

- Nhm u: ch s ca Nitrogene (N) cn cho l v mm non cng nh thn cy lan. Nu thiu cy s cn ci, o ut, l cy vng vt khng xanh ti. Nu bn nhiu l s xanh ngt, cy s mm yu d b bnh, b gy v kh ra hoa.

- Nhm th hai: ch s ca Phosphorous hay Phosphate (K) cn cho r mc mnh, ra nhiu hoa. Nu thiu cy s yu ui, mm cy v r chm pht trin v chm ra hoa v t hoa. Nu bn qu nhiu cy s ra hoa sm, cy chng gi, l s ngn li.

- Nhm th ba: ch s Postassium hay Potash (P) cn cho thn r, gip cho cy hp th cht N, v vn chuyn nha cy d dng t r ti l. Nu thiu cy s khng c cng ct v t hoa, nhng nu qua nhiu, cy s cn ci, ngn ho r, u l gi s b chy.

Phn bn c 2 dng chnh: tc ng nhanh (Fast release) nh phn ha tan trong nc v phn chm tan (Slow release). Loi phn ny l dng v bc c cht polymer cho nhng ht phn bn khng tan ngay trong nc, v tan ra dn dn.

Nn Dng Phn Chm Tan Hay Khng?Ngi ta khuyn co rng:

- Nu dng phn ha tan trong nc, nn bn hng tun vi liu lng rt long ch bng hay tha c ph gt cho 4 lt nc.

- Nu dng phn chm tan ch cn b 2-3 tha c ph trn mt chu rng 6 (15 cm) v mi nm 2 ln l C loi phn ni rng c hiu qu trong 9 thng nh Dynamite v 6 thng nh Osmoscote. Nhng thc t ra sao? my ngi bit r.

Trong cc th phn bn thng c cht mui. Nu c nhiu mui ng li trong chu, lan s b chy r v s lm cy yu ui, ci cc v cht dn. Bn t khng sao, bn nhiu s c hi, v vy gii trng lan c kinh nghim truyn tung cu: Weekly and weakly c ngha l nn bn hng tun v bn phn long.

Nn Dng Phn Chm Tan Hay Khng?Dng phn chm tan c ch c li l bt i cng vic bn phn, nhng c nhiu iu bt tin l:

Th phn ny cn phi trong tnh trang m t vi mt nhit ti thiu l 70F (21C) v mi lm v c v bc ngoi.

Khi nhit ln cao khong 85F (29.4C) m chu li m t, v bc s v v phn bn tit ra nhiu hay t khng sao kim sot c.

Vo ma Xun, khi mm cy mi mc cn phi bn phn cho r v mm cy tng trng mnh m lc ny cy cn nhiu cht Nitrogene. Nhng vo ma ny ti California v nhiu ni khc hy cn lnh cho nn phn chm tan khng v ra c.

Khi tri ma lin tip vi ngy, phn bn s b nc ma tri i mt.

Phn chm tan c tc dng trong 3-4 thng, nhng thng u nng phn bn mnh hn l nhng thng cui.

Phn chm tan c tc dng tt vi nhng loi lc no cng cn m t nh Cymbidium, hay Miltonia nhng bt li i vi loi Dendrobium cn phi c thi gian cho cht trng ri kh ti.

Khng bit chc c nh hng ca phn nhiu hay t. Khng tt vi nhng loi lan cn kh ro v khng cn phn bn trong thi gian ng ngh. Nu c tip tc bn phn, Dendrobium hay Phalaenopsis s ra cy non (Keiki) thay v ra hoa.

Gi bn phn chm tan t hn l phn ha tan rt nhiu.

Cu hi khc ti sao cc nh k ngh trng lan li u chung loi phn ny? Xin tha: Tit kim nhn cng. Vi nh knh v trang b ti tn h c th kim sot c nhit , m , nh sng, thi biu ti nc bn phn trong lc cy mc mnh cng nh trong thi k ngh hoc thc cho lan n theo mun. Do h bn ti a, cho cy ra nhiu, cng v vy khi chng ta mua v cy c tn li dn, l nh hng ca vic bn phn qu .

Trn thi trng hin nay c nhiu loi phn ht do nhiu hng ch to nh: Scotts, Osmocote, Schultz, Dynamite, Miracle-Gro Vy th nn mua loi no? Mu vng, mu xm hay xanh l cy? Nn nh mu sc khng cho ta bit phn ra sao, m cn phi bit r thnh phn cc hp cht trong phn bn. Th d nh: 24-4-8 hay 19-5-5 m bn cho lan ch ra ton l, kh lng c bng.

kt lun xin tm gn trong my cu:

Lan cn bn phn, nhng nn bn rt t.

Bn phn lm sao cho cy mc mnh v ra hoa, khng nn bn qua nhiu lm cho cy tn li.

Cch y my nm mt vi hi vin hi Hoa Lan VN x dng th phn Mac Amp 10-40-6 qu lm cho cy lan tn li v cht dn. l kinh nghim qu bu cho nhng ai khng chu tm hiu thu o vn ti bn m li nghe theo nhng li mch bo v cn c.

Cch s dng phn bn cho LanHoa lan p, qu phi, d thng v c bit c nhng loi gi c hoa rt lu tn, c khi n hng thng, nh loi Dendrobium nn c nhiu ngi chi hoa a thch. Tuy nhin do y l mt loi hoa tng i mi l i vi nhiu ngi chi hoa ti t nn nhiu ngi cha bit cch chm sc chng, v th h c thng thc, ngm nhn nhng bng hoa c sn trn cy khi mi mua v.

Sau t hoa ny tn th khng thy tip tc ra hoa na, hoc c khi mua cy lan con v trng nhng ch mi chng thy chng ra hoa. Qua tm hiu thc t trong nhng ngi chi lan c tnh cht ti t, ti thy: lan khng ra hoa c th do nhiu nguyn nhn, chng hn nh cy cha trng thnh, lan rng c nhp t x lnh v trng x nng trong nguyn nhn khng bn ng loi phn theo yu cu ca tng giai on sinh trng ca cy lan cng l mt trong nhng nguyn nhn thng gp nht.

Cng ging nh nhiu loi cy trng khc mi giai on sinh trng ca cy lan cng cn c mt s lng v t l phn bn thch hp. Nu khng p ng c yu cu ny th qu trnh sinh trng v pht trin ca cy lan s b nh hng, m th hin r nht l vic khng ra hoa, hoc ra hoa nh xu, d rng Trong phn bn ngi ta thng quan tm nhiu n ba nguyn t a lng l m (N), Ln (P) v Kali (K).

m (N) l nguyn t c tc dng lm cho cy tng trng nhanh, ra chi, ra l mnh nn ph hp bn cho cy lan con ang thi k tng trng kch thch cy ra chi non, ra l, ra r lm cho cy pht trin nhanh. Nu thiu m cy s m yu, l nh, gi nua nhanh, l b vng

Phn Ln (P) c tc dng kch thch, thc y qu trnh hnh thnh hoa cho cy lan, ng thi gip cy ny chi v ra r mnh, gi cho hoa rng. Nu thiu Ln cy lan s khng ln, cn ci khng ra hoa c, l xanh m hoc tm, r t pht trin, khng c chi non v cy cng d b bnh.

Phn Kali (K) c tc dng lm cho cy lan cng cp, thc y ra chi mi, gi cho hoa lu tn, mu sc ti p thiu Kali cy lan s khng pht trin c, cy yu t, hoa nhanh tn v mu sc hoa khng p, cy lan d b bnh

Trn th trng hin nay c bn kh nhiu loi phn hn hp c cha nhiu nguyn t a lng v vi lng (vi nhng t l khc nhau). Vi lan, chng ta nn chn v s dng cc phn sau y:

1) NPK 30-10-10: y l loi phn gip cy tng trng mnh (v chng c cha nhiu m). Trong thnh phn ca chng cha ti 30% m, nhng ch c 10% Ln v 10% Kali. Loi phn ny s dng cho cy lan con, chi non mi tch, cy ra r, nhy con, ra l v pht trin thn cy

2) NPK 10-30-10: y l loi kch thch thc y qu trnh hnh thnh hoa (v chng cha nhiu Ln). Trong thnh phn ca chng ch c 10% m v 10% Kali, nhng li c n 30%Ln. Loi phn ny s dng cho cy lan trng thnh kch thch cho cy ra hoa, gip cho pht hoa di, sing hoa v nhiu hoa

3) NPK 10-10-30: Loi phn ny gi cho mu sc ca hoa p v lu tn, v trong thnh phn ca chng c t l Kali rt cao (30%) so vi hai loi phn kia, mi loi ch c 10%. S dng khi xut hin pht hoa, lm cho cy ng vng, vi hoa di, thng, hoa p, lu tn

Ngoi nhng loi phn va nu trn, trn th trng cn c nhiu loi phn hn hp c t l N, P, K khc nhau, chng ta cng c th chn s dng, nhng phi m bo nguyn tc l khi cy cn nh phi dng loi phn c t l m cao gip cho cy tng trng mnh. Khi cy trng thnh phi dng loi phn c t l Ln cao kch thch thc y qu trnh hnh thnh hoa. V khi cy bt u ra hoa th phi dng loi phn c t l Kali cao hoa p v lu tn.

--C th ni Hong Lan (cn gi l Dendrobium hay ng Lan) l ging lan d tnh, d trng, d cho bng v bng rt lu tn, rt ph hp vi nhng ngi mi chi lan, cha c kinh nghim.

Qua m t trong th ca bn, kt hp vi kinh nghim thc t v ging lan ny, chng ti on rng cy lan ca bn khng ra bng c l do loi phn bn ang s dng c t l m, ln v kali (NPK) cha ng vi t l m cy lan yu cu cu giai on sinh trng ny.

Nh bn bit mi giai on sinh trng ca cy lan chng cn c mt s lng v t l phn NPK thch hp. Nu khng p ng c yu cu ny th qu trnh sinh trng v pht trin ca cy s b nh hng m th hin r nht l cy ci cc, khng ra hoa, hoc ra hoa nh xu, d rng

Yu cu v phn bn ca cy lan c th tamh chia ra lm 3 giai on nh sau: Khi cn nh, cy cn nhiu m tng trng v th ta phi s dng loi phn c t l m cao hn ln v kali. Khi cy trng thnh, chng cn nhiu phn ln kch thch thc y qu trnh hnh thnh hoa, gip cho pht hoa di, nhiu hoa, gip cho cy ra chi, ra r mnhv th ta phi s dng loi phn bn c t l ln cao hn m v kali. T khi cy xut hin vi hoa th ngoi ln cy li cn nhiu kali gi cho hoa c mu sc p, rc r v lu tnv th ta phi dng loi phn c t l kali cao hn m v ln.

Cy lan ca bn trng c gn 2 nm, mi iu kin cho cy lan sinh trng tt bn p ng c, cy lan li rt mp mp, xanh tt chng t ang tha m v thiu ln, thiu kali v vy bn nn thay loi phn ang dng bng phn c t l cao nh phn bn l Grow more 10-30-10 hoc Piter 10-30-20, phun ln l nh k 6-7 ngy mt ln. Khi no thy l vi hoa th hy chuyn sang dng phn c hm lng kali cao hn nh Grow more 10-10-13 hoc Piter 15-20-30 gi cho hoa lu tn, mu sc p, rc r.