If you recently planted sunflowers in your yard, you may not have any seeds\nready for harvest just yet. In that case, you are probably wondering when\nsunflowers produce seeds, and if there is anything you can do to help them\nalong.\n\n\n\nSo, when does a sunflower produce seeds? A sunflower produces seeds that are ready for harvest 30 to 45 days\nafter the flowers bloom, and 110 to 120 days after planting from seed. Most sunflowers are annuals, meaning that\nthey live only one year and must be replanted the following year.\n\n\n\nOf course, depending on the variety of sunflower you choose, you may get\nfewer seeds or smaller flowers. Other factors such as crowded spacing,\nover fertilization, and environmental conditions can all affect the quality\n(for example, oil and protein content) of sunflower seeds.\n\n\n\nLet\u2019s take a closer look at sunflowers, when they produce seeds, and the\nfactors that can affect your harvest.\n\n\n\nWhen Do Sunflowers Produce Seeds?\n\n\n\nSunflower seeds generally produce seeds that are ready for\nharvest between 30 and 45 days after they bloom. The time from planting a seed to harvest mature\nseeds is 110 to 120 days.\n\n\n\nSunflower seeds will usually be ready for harvest by 110 to 120 days after planting seeds.\n\n\n\nAccording to Purdue, sunflowers in temperate regions may mature in as little as 109 days. \n\n\n\nOn the other hand, North Dakota State University suggests that the time from planting to maturity is closer to 119 days.\n\n\n\nAccording to the University of Tennessee Extension, \n\n\n\n\u201cSunflower seeds are generally physiologically mature when the back of the flower head is yellow. When the head turns brown on the back, seeds are usually ready for harvest.\u201dUniversity of Tennessee Extension, https:\/\/extension.tennessee.edu\/publications\/Documents\/SP721.pdf\n\n\n\nSo, you should plan on waiting about 3 months for the\nflowers to bloom, and another month after that for the sunflower seeds to be ready\nfor harvest and eating.\n\n\n\nHow Many Seeds Does A Sunflower Produce?\n\n\n\nA single sunflower can produce hundreds or thousands of\nseeds, depending on the size of the plant.\n\n\n\nDepending on the size of the flower, a sunflower can produce hundreds or thousands of seeds.\n\n\n\nSome smaller varieties, such as \u201cTeddy Bear\u201d, only grow 2 to\n3 feet (0.6 to 0.9 meters) tall, with flowers that have a 5-inch (12.7\ncentimeter) diameter.\n\n\n\nLarger varieties, such as \u201cPike\u2019s Peak\u201d, can grow up to 15\nfeet (4.6 meters) tall, with flowers that have a 14-inch (35.6 centimeter) diameter.\n\n\n\nHow Long Do Sunflowers Live?\n\n\n\nMost sunflowers are annuals, meaning that they only live one growing season. You will need to replant sunflowers every year that you want to grow them.\n\n\n\nMost sunflowers are annuals, meaning they only live for one season, and need to be replanted every year.\n\n\n\nAt about 84 days after planting, the flowering on a\nsunflower plant will be complete. By 119\ndays after planting (35 days later), the back of the head of the flower will be\nbrown, and the seeds will be ready for harvest.\n\n\n\nWhat Kind Of Sunflowers Should I Plant?\n\n\n\nWhen selecting a sunflower to plant, make sure to choose one that you can\ngrow in your climate! For more information, check out\nthe USDA Zone Hardiness Map to see what zone you are in.\n\n\n\nHere are some sunflower varieties that you might want to try:\n\n\n\nRudbeckia Indian Summer Sunflower \u2013 this sunflower plant produces gold and yellow flowers that bloom for 12 weeks. The plant reaches a height of 36 to 42 inches, with a spread of 12 to 16 inches. In mild climates, you can sow seeds any time during the year. For more information, check out Rudbeckia Indian Summer Sunflowers on the Burpee website.Pike\u2019s Peak Sunflower \u2013 this giant sunflower plant produces gold, orange, and yellow flowers that bloom for 6 weeks. The plant reaches an astounding height of 12 to 15 feet, with a spread of 26 to 30 inches. The seeds can be as long as 1.5 inches each. For more information, check out Pike\u2019s Peak Sunflowers on the Burpee website.Kong Hybrid Sunflower \u2013 this giant sunflower plant produces gold and yellow flowers that bloom for 6 weeks. The plant reaches a height of up to 13 feet, with a spread of 36 to 40 inches. For more information, check out Kong Hybrid Sunflowers on the Burpee website.Teddy Bear Sunflower \u2013 this dwarf sunflower plant produces gold, green, and yellow flowers that bloom for 5 weeks. The plant reaches a height of 24 to 36 inches, with a spread of 14 to 16 inches. For more information, check out Teddy Bear Sunflowers on the Burpee website.Del Sol Hybrid Sunflower \u2013 this sunflower plant produces brown and yellow flowers that bloom for 6 weeks. The plant reaches a height of 5 to 6 feet, with a spread of 8 to 12 inches. For more information, check out Del Sol Hybrid Sunflowers on the Burpee website.Mammoth Russian Sunflower \u2013 this large sunflower plant produces yellow flowers that bloom for 5 weeks. The plant reaches a height of 9 to 12 feet, with a spread of 36 to 40 inches. For more information, check out Mammoth Russian Sunflowers on the Burpee website.\n\n\n\nRemember: although sunflowers can be transplanted, they are\nsensitive to transplant shock. It is\nrecommended to sow sunflower seeds directly into the soil where they will be\ngrown.\n\n\n\nDo You Need Two Sunflowers To Get Seeds?\n\n\n\nNo, you do not need two sunflowers to get seeds from the\nplants. However, there is some evidence\nthat pollen movement between plants (thanks to bees) can improve sunflower seed\nyield.\n\n\n\nYou do not need two sunflowers to get seeds from the plant, but evidence suggests that yield can increase with bees to help carry pollen between two or more sunflowers.\n\n\n\nHere is an interesting fact about sunflowers: a sunflower is\nnot really one flower, but rather, 1000 or more tiny flowers growing together.\n\n\n\nAccording to Purdue University,\n\n\n\n\u201cThe sunflower head is not a single flower (as the name implies) but is made up of 1,000 to 2,000 individual flowers joined at a common receptacle. The flowers around the circumference are ligulate ray flowers without stamens or pistils; the remaining flowers are perfect flowers (with stamens and pistils). Anthesis (pollen shedding) begins at the periphery and proceeds to the center of the head. Since many sunflower varieties have a degree of self-incompatibility, pollen movement between plants by insects is important, and bee colonies have generally increased yields.\u201dPurdue University, https:\/\/hort.purdue.edu\/newcrop\/afcm\/sunflower.html\n\n\n\nWhat Other Factors Can Affect Growth Of Sunflowers?\n\n\n\nThe quality of care that you give your sunflowers will help to decide how many flowers (and\nseeds) you get each year. Remember that sunflowers need full sun (8 or\nmore hours or sunlight per day).\n\n\n\nOther important factors for sunflowers are temperature, watering,\nfertilizing, and spacing.\n\n\n\nTemperature for Sunflowers\n\n\n\nIn order to germinate properly, soil temperatures for\nsunflower seeds should be at least 50 degrees Fahrenheit (10 degrees Celsius)\nand at most 91 degrees Fahrenheit (33 degrees Celsius).\n\n\n\nThe ideal soil temperature for sunflower seed germination is\n70 to 78 degrees Fahrenheit (21 to 26 degrees Celsius).\n\n\n\nAt these temperatures, sunflower seeds should germinate in 4 to 11 days. For more information, check out my article on sunflower seed germination.\n\n\n\nAccording to the Old Farmer\u2019s Almanac, sunflower seeds should be sown in the soil outside only after the last spring frost has passed.\n\n\n\nYou can find your last spring frost date on the Old Farmer\u2019s Almanac website.\n\n\n\nWatering For Sunflowers\n\n\n\nSunflowers are naturally resistant to both drought and heat, so you may only\nneed to water deeply once per week, to encourage a strong and extensive root\nsystem.\n\n\n\nWater your sunflowers deeply and infrequently, to encourage strong and extensive root systems.\n\n\n\nIt will be difficult to under water them unless you really neglect your\ngarden during a heat wave, or have very dry soil.\n\n\n\nIf you have a problem with dry soil, check out my article on dry soil.\n\n\n\nOn the other hand, over watering can spell death for your sunflowers, due to\nroot rot or fungal diseases. For more information, check out my article on over watering.\n\n\n\nFertilizing For Sunflowers\n\n\n\nBefore you plant a sunflower, add some compost to your soil. It will\nprovide organic material and nutrients for your sunflower as it grows. \nThe best part is that you can make compost yourself from ordinary yard and kitchen\nwaste!\n\n\n\nCompost is a great way to provide nutrients and organic material to your soil, while recycling kitchen scraps and yard waste.\n\n\n\nFor more information, check out my article on how to make your own compost.\n\n\n\nIt may be necessary to use fertilizers as a supplement to compost, in order\nto provide extra nutrients if your soil is lacking. The best way to tell if you\nneed fertilizer is with a soil test.\n\n\n\nFor more information, check out my article on soil testing.\n\n\n\nA soil test will also indicate the pH of your soil. The ideal pH range\nfor sunflowers is between 6.0 (slightly acidic) and 7.5 (slightly basic).\n\n\n\nIf your soil pH is too low (acidic), you can add lime (calcium carbonate) to\nraise it.\n\n\n\nIf your soil pH is too high (basic), you can add sulfur to lower it.\n\n\n\nSpacing for Sunflowers\n\n\n\nSunflower seeds should be planted at most 1 inch (2.5\ncentimeters) deep, with about 6 inches (15 centimeters) between each seed in\nthe row. The rows themselves should be\nabout 30 inches (76 centimeters) apart to leave room for watering, weeding, and\nharvesting later in the season.\n\n\n\nSupport for Sunflowers\n\n\n\nSome giant varieties of sunflowers can grow to 12 feet tall\nor higher. As such, you may need to\nprovide some support to keep them from falling over due to their own weight.\n\n\n\nThere are lots of ways to do this, including tying the sunflowers to a stake or trellis as they grow. For more information, check out my article on supporting plants, and my article on trellises.\n\n\n\nConclusion\n\n\n\nBy now, you have a good idea of when sunflowers will produce seeds. \nYou also know a bit more about how to take care of sunflowers and how to avoid\nthe problems that can affect your harvest.\n\n\n\nI hope you found this article helpful \u2013 if so, please share it with someone\nwho can use the information. If you have any questions to ask or advice to\nshare about sunflowers, please leave a comment below.