What to plant in May in Siena This page summarizes what is worth doing in May in Siena, using typical weather for the period and local sowing and transplanting windows.
Summary Recommended direct sowing 13 Indoor seed starts 14 Recommended transplants 8 Crops to wait on 0 May in Siena is a month rich in garden options. There are 23 useful crops: Swiss chard, Broccoli, Carrot, Tuscan kale, Cucumber, Onion, Green bean, Fennel, Strawberry, Lettuce, Eggplant, Potato, Pepper, Pea, Tomato, Parsley, Radish, Rosemary, Arugula, Sage, Spinach, Pumpkin, Zucchini. The same card can combine direct sowing, indoor seed starts, transplanting when they overlap in the month.
Before starting, watch especially for: overall climate risk is moderate.
Crops for this month Each crop appears once. Inside the card you can see the useful options for the month, such as direct sowing, indoor starts, transplanting, or a cautious wait.
Direct sowing: all MayEstimated harvest: from June 19 to July 19Success probability: 100%Climate attention: high heat, high dry spellStart indoors: all MayExpected transplant: 42 days after sowing (from April 20 to September 3)Transplanting: all MayEstimated harvest: from June 29 to July 29Success probability: 100%Climate attention: high heat, high dry spellDirect sowing: all MayEstimated harvest: from June 29 to July 29Success probability: 100%Climate attention: high heat, high dry spellDirect sowing: all MayEstimated harvest: from June 24 to July 24Success probability: 100%Climate attention: high heat, high dry spellStart indoors: all MayExpected transplant: 35 days after sowing (from April 5 to September 21)Transplanting: all MayEstimated harvest: from June 24 to July 24Success probability: 100%Climate attention: high heat, high dry spellStart indoors: from May 24 to August 5Expected transplant: 21 days after sowing (from June 14 to August 26)Direct sowing: all MayEstimated harvest: from July 29 to August 28Success probability: 100%Climate attention: high heat, high dry spellStart indoors: all MayExpected transplant: 77 days after sowing (from March 24 to August 22)Transplanting: all MayEstimated harvest: from July 29 to August 28Success probability: 100%Climate attention: high heat, high dry spellDirect sowing: from May 29 to May 31Estimated harvest: from July 17 to July 19Success probability: 80%Climate attention: high dry spellDirect sowing: from May 5 to May 31Estimated harvest: from July 3 to July 29Success probability: 80%Climate attention: high heat, high dry spellStart indoors: all MayExpected transplant: 35 days after sowing (from May 5 to September 3)Transplanting: from May 5 to May 31Estimated harvest: from July 3 to July 29Success probability: 80%Climate attention: high heat, high dry spellStart indoors: all MayExpected transplant: 28 days after sowing (from April 11 to September 15)Transplanting: all MayEstimated harvest: from June 29 to July 29Success probability: 100%Climate attention: high heat, high dry spellDirect sowing: all MayEstimated harvest: from June 4 to July 4Success probability: 100%Climate attention: high heat, medium dry spellStart indoors: all MayExpected transplant: 28 days after sowing (from April 20 to September 28)Transplanting: all MayEstimated harvest: from June 4 to July 4Success probability: 100%Climate attention: high heat, medium dry spellStart indoors: from May 2 to June 6Expected transplant: 56 days after sowing (from June 27 to August 1)Direct sowing: all MayEstimated harvest: from July 29 to August 28Success probability: 100%Climate attention: high heat, high dry spellStart indoors: all MayExpected transplant: 56 days after sowing (from June 15 to August 13)Direct sowing: all MayEstimated harvest: from June 24 to July 24Success probability: 100%Climate attention: high heat, high dry spellStart indoors: from May 3 to July 3Expected transplant: 42 days after sowing (from June 14 to August 14)Direct sowing: all MayEstimated harvest: from July 19 to August 18Success probability: 90%Climate attention: high heat, high dry spellDirect sowing: all MayEstimated harvest: from May 25 to June 24Success probability: 100%Climate attention: medium heat, medium dry spellStart indoors: all MayExpected transplant: 42 days after sowing (from May 11 to September 3)Transplanting: May 11, from May 16 to May 31Estimated harvest: July 9, from July 14 to July 29Success probability: 80%Climate attention: high dry spellDirect sowing: all MayEstimated harvest: from May 25 to June 24Success probability: 100%Climate attention: medium heat, medium dry spellStart indoors: all MayExpected transplant: 42 days after sowing (from April 24 to September 3)Transplanting: all MayEstimated harvest: from June 29 to July 29Success probability: 90%Climate attention: high dry spellDirect sowing: all MayEstimated harvest: from June 4 to July 4Success probability: 100%Climate attention: high heat, medium dry spellStart indoors: from May 24 to July 10Expected transplant: 21 days after sowing (from June 14 to July 31)Start indoors: from May 24 to August 6Expected transplant: 21 days after sowing (from June 14 to August 27)Why the calendar changes Late frosts Estimated cautious last frost: April 19 . Around this window, protect sensitive transplants and avoid moving warm-season sowings too early.
Climate risk for the month Average minimum temperature 10.4 C Average maximum temperature 22.24 C Average temperature 16.29 C Average rain 55.49 mm Average dry spell 10.9 days Average solar radiation 21.11 overall climate risk is moderate FAQ Which crop has the clearest window in May in Siena? Start with Swiss chard for direct sowing during from May 1 to May 31. The estimated harvest is from June 19 to July 19 and the best estimated success rate is 100%.
Should I use indoor seed starting in May in Siena? For Broccoli, the useful indoor seed period is from March 9 to July 23. The expected transplanting window is from April 20 to September 3 and it is best to start seedlings 42 days earlier.
What should I watch in May in Siena? Check irrigation and soil moisture: the average dry spell reaches 10.9 days, even with average rain of 55.49 mm. Monthly averages: minimum 10.4 C, maximum 22.24 C, rain 55.49 mm, and dry spell 10.9 days.
Sources and limits Use these dates as practical guidance, not fixed deadlines. Exposure, soil, containers, irrigation, and the next few days' forecast can move the right timing earlier or later.
Municipality registry: ISTAT Local historical climate: NASA POWER Daily API Representative weather point: GeoNames Crop needs: OrtoClima Last data update: May 10, 2026 Related pages
