Little research is reported on container production of ornamental lotus (Nelumbo nucifera Gaertn.). In this study, fertilization has a critical impact on growth index of lotus `No.7', a numbered clone, in 29 liter (7.5 gallon) containers. Compared to the control treatment (zero fertilization), 1–3 tsp. (4g/tsp.) of 20-10-20 (Pro·Sol) applied every 20 days significantly increased plant height (1.3–1.6 times), fresh biomass (2.4–3.3 times), emerging leaf number (1.9–2.7 times), flower number (2.4–2.7 times), and propagule number (1.3–1.5 times). There was a quadratic response as growth parameters increased with increasing fertilizer rates. Growth indices increased linearly from 0–2 tsp. and then leveled as fertilizer rates reached 3 tsp. No difference was recorded in flower number and plant height for 1–3 tsp. fertilizer treatments. Absorption of nutrition increased with fertilization concentration, an absorption peak value appeared between 13 July and 2 Aug. For 1-3 tsp. treatments, nitrogen is nearly 100% absorbed by lotus every 20 days. However, there is some residue for P and K, especially in 3-tsp. treatment in the earlier and later growth season. Analysis of young leaf tissue indicated that macronutrients N, P, K, and dry mass increased, but Ca decreased with increasing fertilizer rates. In tuber tissue, K, Na, and dry mass increased, while Ca and Fe content decreased. The most efficient rate of fertilizer for 7.5 gallon container production of `No.7' lotus was 2 tsp. per 20 days. Although soluble fertilizer also stimulated proliferation of algae growth in the early growth stage of lotus, this problem dissipated as emerging leaves shaded the water surface.
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