This study investigated the effects of planting density, container size and period of raising seedlings on the growth and flowering of non-pinched snapdragons. In experiment 1, seeds were sown in July, September or February, and seedlings were planted at a density of 50 or 100 plants per square meter. When sown in July and September, plant heights exceeded sufficiently 100 cm to satisfy the highest quality of cut flowers from that locality. Weight of cut flowers and the number of axillary buds decreased at the higher planting densities. But there was no effect of planting density in a culture system sown in February. Eexperiment 2 investigated the effects of container size (deep or shallow type) and nursery period (21, 32 or 43 days) on the growth and flowering of non-pinched snapdragon cultivars 'Maryland Pink' and 'Light Pink Butterfly II'. Days to anthesis and the length of cut flowers of 'Maryland Pink' decreased in deep type containers. The growth of 'Light Pink Butterfly II' was not affected by the container size. There was no adverse effect of nursery periods up to 43 days on either cultivar.

Effects of pinching positions (just above the first, second, third and fourth node) on the growth and flowering of snapdragons (Antirrhinum majus L.), 'Maryland Pink' and 'Light Pink Butterfly II', were investigated. Seeds were sown in July and seedlings were raised without temporary planting. The main shoots were pinched at different node positions in September. The results were compared with those of the conventional cultivation with temporary planting. First flowering of lateral shoots in the third and fourth node pinching was earlier than in other pinching positions. The number of cut flowers was increased with upper pinching positions. The length of cut flowers in the primary lateral shoots from the fourth node was shorter than those from the other nodes. When cut flowers from the same node positions were compared, the length was shorter in 'Light Pink Butterfly II' than in 'Maryland Pink'. Although second node pinching is conducted in the conventional commercial cultivation of snapdragons in Japan, we suggested that upper node pinching might be suitable for higher productivity in the cultivation without temporary planting. Pinching at the first, second, third and fourth nodes without temporary planting all resulted in more cut flowers than second node pinching under conventional cultivation (with temporary planting). These findings showed that suitable positions for pinching the main stems were just above the second or third node for 'Maryland Pink', and the second node for 'Light Pink Butterfly II'.

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