Protected strawberry culture at high altitude temperate climate as influenced by planting time, mulching and soil moisture

An experiment was conducted on growing strawberry under polyhouse environment having three planting dates (mid September, mid October and mid November), and three types of mulches (black and clear polyethylene and grass straw (Cymbopogon martini) and without mulch as control). Irrigation level/week was kept constant for each replication. Runners planted in mid September and beds mulched with black polyethylene improved fruit quality with comparatively better size (3.0 cm length, 2.9 cm dia. and 11.7 g) and was also effective in retaining better amount of soil moisture for longer duration even on the 7^th day after irrigation with 30.3% in rainy season to 18.4% in summer. This treatment combination also improved plant growth, i.e., 37.0 cm plant spread, 58.4 cm² leaf area and 36.5% dry matter and 159.0 g fruit yield/plant. Grass mulch in combination with September planting time was effective in improving plant growth in terms of plant spread (37.0 cm), leaf number/plant (19.1), leaf area (62.3 cm²) and dry matter (36.2%) as well as fruit physico-chemical properties like TSS (10.8⁰Brix), total sugars (7.5%) and ascorbic acid (44.1%). Moisture retention was the lowest (18.5%) in summer in comparison to rainy season (31.3%) even under black polyethylene mulch irrespective of planting time depicting the seasonal effect on the soil moisture content. Clear polyethylene encouraged weed growth (355.3–362.8 weeds/bed). Highly significant positive correlations were recorded among soil moisture, plant dry matter and different growth and fruit characters. Leaf area and number of leaves/plant positively influenced fruit size, weight and fruit yield/plant which can be used for prediction of fruit yield of strawberry.