Euphorbia pulcherrima Willd. Ex. Klotzsch 'Gutbier V-14 Glory' plants
were grown with N at 220 mg.L-1 (20N-4.4P-16.6K) using hand (HD), micr
otube (MT), ebb- and-flow (EF), and capillary mat (CM) irrigation syst
ems and were irrigated either daily (daily = D) or as needed (intermit
tent = I). For all irrigation systems, daily irrigation produced plant
s with the greatest total dry mass and reduced the amount of nutrients
lost as runoff, but plant quality was reduced in one of two years due
to excessive, weak growth. Plants irrigated by MT-D and EF-D had the
greatest total dry masses. HD produced lower total plant dry mass than
all other irrigation systems and frequencies. Runoff from MT-D and EF
-D treatments had the lowest concentration of NO3-N, NH4-N, and PO4-P.
The MT-D, EP-D, and EF-I treatments were the most water-efficient, wh
ereas the CM system had the lowest water efficiency and used the great
est amount of water. Daily irrigation with the MT or EF systems produc
ed optimum plant growth, but intermittent MT irrigation was more water
-efficient. Daily irrigation is a viable production system, but only w
here water conservation is not a concern.