The Right Time for Onions Quiz Quiz

Discover key facts about the best sowing times and practices for onions in horticulture. Test your knowledge of seasonal timing and planting methods to maximize onion yield.

1. Best Season for Onion Sowing

   Which season is generally considered best for sowing onion seeds in temperate regions?

   1. Autumn
   2. Summer
   3. Spring
   4. Winter

   Explanation: Spring is ideal for sowing onions in temperate areas as the soil is workable and the temperatures support germination. Winter is usually too cold for good seedling development. Autumn planting can work in mild climates but often risks frost damage. Summer heat is usually too intense for young onion plants.

2. Optimum Soil Temperature

   At what soil temperature do onion seeds germinate best for successful sowing?

   1. 27°C to 32°C
   2. 13°C to 24°C
   3. 1°C to 5°C
   4. 5°C to 10°C

   Explanation: Onion seeds germinate best when soil temperatures are between 13°C and 24°C, which allows fast and uniform sprouting. Colder ranges slow germination, and hotter soil can cause poor establishment. The extremes outside this range either delay or hinder seedling emergence.

3. Direct Sowing vs Transplanting

   What is a common practice for onion production when planting time is limited or climate is cooler?

   1. Plant bulbs directly in frozen soil
   2. Start seeds indoors for transplanting
   3. Sow seeds only outdoors
   4. Delay sowing until midsummer

   Explanation: Starting seeds indoors for later transplanting helps onions get a head start in regions with short growing seasons or cool climates. Sowing only outdoors can limit success if the season is too brief. Delaying until midsummer or planting in frozen soils is not effective.

4. Rain and Sowing Time

   Why should heavy rainfall periods be avoided when sowing onion seeds?

   1. Seeds risk washing away
   2. Rain improves seed germination
   3. Rain increases seedling vigor
   4. Onions need waterlogged soil

   Explanation: Heavy rain can wash away seeds or cause uneven emergence, which reduces plant stands. Moderate soil moisture is best for germination; waterlogging can harm onion seeds. While water is needed, excessive rain does not improve vigor or germination.

5. Photoperiod Influence

   How does sowing time affect onion bulb development regarding day length (photoperiod)?

   1. Photoperiod has no effect on onions
   2. Proper timing matches bulb formation to longer days
   3. Bulbs form best only in constant darkness
   4. Short days always increase bulb size

   Explanation: Onions require specific day lengths to initiate bulb formation; sowing at the right time ensures bulbing coincides with appropriate daylight. Bulb growth does not occur in constant darkness, and short days do not universally increase bulb size. Photoperiod is a key factor in onion development.