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Adequate amount of water is critical to successful tree nursery operation among resource-constrained smallholder farmers in Africa. Two experiments were undertaken with the objectives of evaluating effects of water application rate and frequency on seedling growth and survival of Persea americana and Vangueria infausta. In experiment 1, water was applied to seedlings at 500 ml per 1 L polyethylene bag daily and at two, four and six day intervals. In experiment 2, water was applied to seedlings every two days at the rate of 25, 50, 100 and 150 ml per polyethylene bag. The results indicated that V. infausta was more responsive to the rate than frequency of water application. Water application of 100 ml every two days was effective in promoting seedlings growth and survival for both species. Application of 500 ml of water every two days promoted growth of P. americana, while watering frequency had no significant effect on V. infausta. It is concluded that V. infausta seedlings require less frequent watering. Both species could be successfully raised with 100 ml of water applied every two days.Key words: Nursery irrigation, nutrient reserves, root collar diameter, seedling mortality.

The use of appropriate growing medium has been an important factor influencing growth and survival of seedlings in the nursery. Raising Uapaca kirkiana rootstocks from seeds has been a challenge aspencil-size stem thickness is required before grafting can be done. An experiment was carried out with the objective of determining an effective growing medium that ensures survival and rapid growth of U.kirkiana seedlings. Ten different combinations of sand, forest soil and sawdust amended with four different levels of nitrogen, phosphorus and potash fertilizer were evaluated. The result showed that thegrowing medium comprising 75% forest soil and 25% sawdust produced the tallest seedlings with larger root collar diameter and higher survival at ten months after planting. Amending the samegrowing medium with fertilizer improved the root collar diameter of the seedlings. It is concluded that a growing medium comprising 75% forest soil and 25% sawdust and amended with NPK fertilizer wassuperior in improving U. kirkiana seedling growth to attain a suitable diameter for grafting within ten months.