Tropical Seeds Planting
Germinating tropical seeds can be both exceedingly easy, and very tricky. Certain seeds begin to sprout inside the fruit as it ripens. Many other seeds go into a period of dormancy that must be broken for them to germinate. Considering that “tropical seeds” encompass plants growing in such varying, but often subtlely different climates, there are a number of different strategies for germinating tropical seeds in your garden. Below we list a number of species, with general and specific tips on germination. The only constant requirement for pretty much any seed is to keep the soil temperature warm, usually about 75-85F. Always remember, tropical seeds are not the same as the tomato, vegetable and flower of seeds you might find at a local garden store. They have widely varying germination times that can range anywhere from the Ice Cream Bean (Inga edulis), which germinates while still inside the fruit, to many types of palms, which average up to 9-12 months for germination. Fortunately the latter is the exception, not the norm. Germinating the exotics can be quite fun and extremely rewarding, but often requires a different mindset and different approach than that used for germinating the common garden annuals. Exotic Seed Baks
Garden Vegetable and Flower Seeds
Standard garden annuals, plants such as tomatoes, peppers, corn, poppies, lettuce, etc. are in general, some of the easiest seeds to germinate. A world apart in germination ease from some of the tropicals, most will germinate rapidly (within days to a week or two) under standard conditions. A few, such as the peppers can be trickier, so read some of our comments below. For the most part, garden annuals need minimal pre-treatment and germinate fairly well in regular soil and with moderate water. Soil temperature requirements vary, with certain seeds such as tomatoes and peppers germinating best in warmer soils and others such as lettuce, may germinate well in cooler soils.
A Note on Our Seeds
We take the utmost care in handling and delivering fresh seeds. our pride ourselves on the quality and diversity of the seeds we offer and we routinely test our seeds for viability and germination. We never are going to send you old, musty seeds that have been laying on a shelf for years. The use the very same seeds we send to customers to germinate our own plants. Our product offerings have a lot of turnover, specifically because we strive to offer seeds in season and keep storage of seeds at a minimum. We at Trade Winds Fruit greatly value your business and wish you all the best in your gardening endeavors!
Other general tips and notes:
– For difficult to germinate or hard-coated seeds, soaking seeds in a warm, moist paper towel, or in warm water, for 24 hours prior to planting also helps to break dormancy.
– Keep the soil warm! Many tropicals, just like tomatoes (which are originally from the tropics) require night time soil temperatures to be warm for germination. Even if your day time highs are well into the 70’s, the soil may cool off so much at night that the seeds never start.
– Also note that many tropical seeds may be planted in sub-optimal conditions, only to germinate months (sometimes even a year or more) later when the soil warms up, or conditions are more favorable. Passiflora seeds are notorious for this.
– For tropical seeds: don’t store seeds for extended periods of time. They are best planted sooner than later. While some varieties, e.g. Passiflora can be stored for several months or up to a year or two, many tropical seeds loose viability much faster. Some types may last only a few days or weeks. Particularly short viability seeds are always noted on package instructions, but in general, all seeds should be planted as quickly as is reasonable. Germination rates will decrease over time.
– Giberellic acid may also be applied for seeds that are more difficult to germinate.
Temperate Seeds: A few require cold-stratification for germination. We’ve tried to include this information when available, but proper cold-stratification generally requires a few weeks to a few months of the seeds stored at refrigerator temperatures prior to planting.
Tropical Fruit, Ornamental, Perennial, Herb Seeds
| Species | Germination Time | Difficulty | Notes |
| Acacia species | 3-4 weeks-A few months | M | Seeds are best soaked in room temperature water for 24 hours prior to planting. Some methods include lightly scarifying the seed coat, but care should be taken to not harm the embryo inside. Seeds should then be planted in sterilized soil at 75-85F. Germination times vary, with some seeds showing quick germination within a couple of weeks and some requiring a few months. |
| Aegle marmelos | 3-8 weeks | E | Use warm (75-90F) soil. Do not overwater, seeds are sensitive to rot. Water when soil surface begins to dry. |
| Annona species | 2 weeks- 4 months | E-M | Break dormancy with warm soil, or pre-soak. Sprouting usually begins 1-3 months later, but can take longer. |
| Artocarpus species | 1-3 weeks | Seeds should be planted immediately. Germination usually begins within a week or two in warm soil. | |
| Asiminia triloba | 1-6 months | M-H | May benefit from cold stratification in moist peat or soil at 34-42F for several weeks prior to planting. Upon planting, use warm soil (70-85F), keep moderately moist. Germination can be slow and a bit erratic, usually averaging a couple of months. |
| Berberis species | 3-12 months | M-H | Extremely variable. Seeds of most species benefit from cold stratification storage at 34-40F for several weeks prior to planting. Seeds are very slow to germinate and tend to show highly erratic germination times. |
| Billardiera longiflora | 1-12 months | M-H | Dried seeds are slow and erratic in germination time. Best germination seems to happen with day/night soil temperatures around 70F/60F, though some sources suggest using warmer soil. Use very well drained soil, keep humidity moderate to high. Can take up to a year to germinate. |
| Bomarea species | 1-9 months | M | Extremely variable. Seeds sometimes germinate within a few weeks but may go dormant and require several months. Moderate temperatures seem best for germination (60-75F). Seeds germinate well in peat. |
| Borojoa patinoi | 3-8 weeks | E-M | Use warm (75-90F) soil. Do not overwater, seeds are sensitive to rot. Water when soil surface begins to dry. |
| Brosimum species | 2-4 weeks | Seeds usually begin germination upon removal from the fruit. Root growth begins almost immediately, shoot growth can take a couple weeks longer. | |
| Brugmansia species | 2-8 weeks | E-M | Variable. Plant at 70-80F. Germination usually takes at least a couple of weeks, but can take up to a couple of months. Different species show varying germination times. |
| Carica species | 2-6 weeks | E | Generally sprouts in 2-6 weeks. Will take much longer if soil temperature is cool. |
| Casimiroa species | 2-4 weeks | E | Generally sprouts in 2-4 weeks. Will take much longer if soil temperature is cool. |
| Citrus species | 2 weeks- 6 months | M | Can take a couple of weeks up to 3-6 months to sprout. Make sure the soil is warm (75-85F), make sure soil is sterile. Dried citrus seeds must break dormancy to germinate, which can be tricky and time consuming. |
| Citrus Blood Oranges | 2 weeks- 6 months | M | Blood oranges often come true to seed, unlike some other Citrus sinensis varieties. Most major blood orange varieties are usually seedless, but will produce some seeded fruits. Fruiting takes 6-12 years from seed. Follow planting directions for general Citrus. |
| Coffea species | 1 week- 3 months | E-M | Variable, tend to be picky about warm temperatures. Keep soil at least 75F, seeds will usually then sprout in a few weeks. Dormancy can be be tough to break so seeds often take up to a few months to sprout. |
| Datura species | 2-6 weeks | E | Warm (75-85F), wet soil is usually sufficient for reasonably fast germination. |
| Eugenia species | varies | Many Eugenia species are marginally hardy, or subtropical. Seeds can take several weeks to begin root growth, and longer for shoot growth. Seeds can vary quite a bit, and some may begin sprouting almost immediately. | |
| Eugenia stipitata Eugenia victoriana | 2-6 months | M | |
| Garcinia species | 1-4 weeks | Plant immediately. Germination is generally slow, but quick. Seeds of some species occasionally produce shoots prior to roots. Warm soil (75-85F) is a must. Don’t overwater but keep moderately moist. Plant in shade. | |
| Helianthus species (Sunflowers) | 1-2 weeks | E | Warm (65-85F), wet soil is usually sufficient for fast germination. |
| Inga species | 1-3 weeks | E | Usually begin root and shoot growth while still inside the fruit. Plant immediately. |
| Ixora species | 4-12 weeks | M | A bit slow to germinate in our experience. Warm to hot soil seems to work best. Water moderately. |
| Jaltomata species | 2-6 weeks | E | Seeds usually germinate within 2-6 weeks at 75-85F. |
| Lactuca virosa | 2-4 weeks | E | Warm (65-85F), wet soil is usually sufficient for fast germination. A bit slower to germinate in our experience than typical garden lettuce. |
| Litchi chinensis | 1-4 weeks | Plant immediately. Do not dry. Seeds generally begin germination rapidy in moist, warm (75-90F) soil. | |
| Luffa species | 2-6 weeks | E | Warm (75-85F), wet soil is usually sufficient for fast germination. Generally a bit slower to germinate than common melons. |
| Macadamia species | 1-5 months | M | Pre-soaking speeds germination. Also consider scarification (cutting) of hard outer shell to allow water to penetrate the interior. If scarification is performed, extra care must be kept to make sure the soil is sterile so fungus and bugs will not eat the seed kernel. |
| Malpighia species | 3-12 months | H-VH | Very erratic and slow germination. Some seeds may germinate quickly, others may take up to 12 months and longer. Plant in moderately moist soil, at 70-85F. Use well drained soil and do not overwater. |
| Marlierea species | 4-16 weeks | E-M | Variable, some seeds sprout within a few weeks, others take much longer. |
| Morinda citrifolia | 6-12 months | M | Reliable, though very slow germination. Minimum time required is usually 6 months. Soil needs to be warm (75-90F) and moderately moist. |
| Ocimium species (Basil) | 1-4 weeks | E | Warm (70-85F), wet soil is usually sufficient for fast germination. |
| Papaver species (Poppies) | 1-4 weeks | E | Warm (65-80F), wet soil is usually sufficient for fast germination. Hot temperatures sometimes inhibit germination. |
| Passiflora species | 3 weeks- 8 months | M | Variable. Warm water pre-soak is highly recommended. Some people will soak in very warm, (+140F) water for a short period of time to break dormancy, although care should be taken not to kill the seed embryo. Seeds tend to be killed around 170-180F. Once dormancy is broken, seeds may germinate within 3-12 weeks. Seeds with delayed breaking of dormancy generally take 3-8 months to germinate. |
| Physalis species | 2-6 weeks | E | Seeds usually germinate within 2-6 weeks at 75-85F. |
| Psidium species | 1 week- 4 months | E-M | Variable, some seeds sprout within 1-3 weeks, others take much longer. Soil must be at 70-85F for reliable germination results. |
| Puya species | 3 weeks – 3 months | M | Varying germination times. Use warm soil (75-85F) and lightly water. Seeds are prone to rot. Water when soil surface begins to dry. |
| Ribes species | 3-12 months | M-H | Extremely variable and often difficult. Seeds of most species benefit from cold stratification storage at 34-40F for several weeks prior to planting. Seeds are very slow to germinate and tend to show highly erratic germination times. |
| Rubus species | 3-12 months | M-H | Extremely variable and often difficult. Seeds of most species benefit from cold stratification storage at 34-40F for several weeks prior to planting. Seeds are very slow to germinate and tend to show highly erratic germination times. |
| Sapindus species | 1-4 months | E-M | Seeds have a hard seed coat; some sources suggest scarifying. We have had luck either way. Use warm (75-85F) soil. |
| Solanum melongena | 2-6 weeks | E | Seeds usually germinate within 2-6 weeks at 75-85F. |
| Solanum quitoense | 4-8 weeks | E | Seeds usually germinate within 2-6 weeks at 75-85F. |
| Solanum sessiliflorum | 4-8 weeks | E | Seeds usually germinate within 2-6 weeks at 75-85F. |
| Solanum uporo | 2 weeks – 4 months | E | Variable. Use warm (75-90F) soil. Seeds can go into a sort of dormancy. Warmth and humidity speeds germination. |
| Synsepalum dulcificum | 1 week – 3 months | Germination often begins quickly but can be extremely slow when it starts. May take a few weeks for roots to begin to develop and longer for a shoot to break the soil surface. | |
| Syzygium species | 1-4 weeks | Tropical ones tend to have seeds that must be planted immediately upon harvest, and will usually begin growing roots within days. e.g. S. aromaticum, S. mallacense Subtropical species, or marginally hardy tropical species, have seeds that can often be stored a few months, and usually break dormancy in warm soil. Most will begin root growth in a few weeks, although shoot growth can take a bit longer. e.g. S. cordatum, cuminii, jambos, oleosum, paniculatum | |
| Theobroma species | 1 week – 1 month | Seeds cannot be stored and should be planted immediately. Do not expose to temperatures below 50F. Seeds sprout best at 75-90F, with high humidity. | |
| Ugni species | 3 weeks- 4 months | M | Variable, some seeds sprout within a few weeks, but generally take quite a bit longer. |
| Vaccinium species | 1-12 months | M-H | In general, Vaccinium, show very slow and erratic germination. Cold stratification for most species is helpful. Stratify for 2-4 months at 36-42F (refrigerator). For many species, the germination rate increases the longer the stratification. Soil need to be at 60F or above, preferably near 70F. Germination generally does not occur with soil temperatures below 55F. The seeds are very small, so care should be taken to keep soil adequately moist so seeds don’t dry out. |
| Zizyphus species | 1-6 months | M | It is recommended to carefully cut, or crack open the hard seed coat. |
Vegetable Seeds (Detailed Instructions)
| Species | Germination Time | Seed Depth | Soil Temp | Notes |
| Artichokes | 2-4 weeks | 1/4-1/2″ | 70-80F | Artichoke seeds are most commonly planted indoors for outdoor transplant. Artichokes grow best in cooler areas and plants will need at least two weeks of 32-50F temperatures to properly set buds, so plan accordingly. Sowing seeds: In milder winter areas where temperatures do not drop below 15F, seeds can be planted in the fall season for a spring harvest. In mild or cold winter areas, plant seeds in the spring, for fall harvest. Seeds should be sown in small containers or flats, planted at 1/4-1/2″ deep. Use a well-drained, sterile potting mix. Seeds germinate best with soil temperatures at 70-80F. Keep soil moderately moist, do not overwater or let soil completely dry out. Germination time under proper conditions runs about 2-4 weeks. Transplanting, Care of Seedlings: Once sprouted, seedlings should be allowed to mature for up to 6-8 weeks before transplanting. Transplant to garden in well-drained soil and protect young plants from freezing temperatures. Make sure to transplant so young plants will receive a minimum of two weeks of cool weather, which will promote budding. Thin plants to 2-3′ and rows to 3-4′. Water regularly. |
| Beans | 1-2 weeks | 1/2-1″ | 70-90F | Bean seeds are generally some of the easiest seeds to sprout. Beans can be planted directly in the ground once the soil has sufficiently warmed, or started in small containers (either indoors or outdoors) for transplanting when plants grow larger. Sowing seeds: Plant seeds in well-drained, sterile soil at 1/2-1″ deep. Keep soil moderately moist and do not let completely dry out. While beans usually germinate quickly, take some care not to over water soil. Non-sterile soils, if over watered, can promote the growth of fungus or pests which may damage the germinating seed. Plant outdoors once the danger of frost has past or in small containers for a later transplant. Care of seedlings: Grow plants 2″ apart, in rows 24-36″ apart. Pole beans will need some type of support, so use a trellis, twine netting, or some similar structure. Plant seeds every 2-3 weeks for continuous production throughout the warmer months. Estimated germination time under optimal conditions: 7-14 days. |
| Corn | 1-2 weeks | 1/2-1″ | 70-85F | Corn seeds are usually quite easy to germinate with with proper soil temperatures. A good method for germination is to place seeds in small containers, either nursery flats or small pots. Standard potting soils or peat both work fine. If starting seed indoors, plant 3-4 weeks prior to the expected date of last frost. Seedlings should only be planted outside once the danger of frost has past. Plant seeds from 1/2-1″ beneath the soil surface. Gently cover with soil. Keep soil temperature above 70F for best germination results. Cool or cold soils can significantly delay or inhibit germination. Once seedlings have sprouted and grown a few inches tall, they can be transplanted to the ground. Alternatively, seeds can be planted directly in the ground if soil temperatures exceed 60-65F and the danger of frost has past. Once seeds have sprouted, thin plants to 8-12″ apart and rows to 24-30″ apart. Estimated germination time under optimal conditions: 7-14 days. |
| Cucumbers | 2-4 weeks | 1/2″ | 70-85F | Cucumber seeds are usually pretty easy to germinate, though an occasional variety may take longer than others. Melon seeds enjoy warm germination temperatures, so be sure to plant when adequate heat is available to warm the soil. Sowing seeds. Cucumber seeds should be started in small containers approximately one month prior to the desired outdoor planting date. Cucumber plants are frost sensitive so (in colder areas) be sure to time seed planting so transplanting seedlings takes place after the date of last frost. Sow seeds 1/2″ deep in small containers (up to 3″ pot size). Plant 1-3 seeds per container. Keep soil temperature between 70-85F. If soil temperature cools too much, seeds may germinate slowly or not germinate at all. Water regularly, when the soil surface begins to dry just a bit. Do not overwater seeds as perpetually dripping wet soil can promote the growth of fungus and bacteria which can kill the seed embryo. Most cucumber seeds germinate in 2-3 weeks, though some varieties can take slightly longer. Transplanting. Cucumbers enjoy warm air temperatures and regular watering. The plants also enjoy warm soil temperatures, preferably above 70F. If soil is not warm enough, several techniques can be tried. Covering the soil with black landscape fabric will raise soil temperatures. Cut a small hole for the melon plant. Another method is to amend the soil with 4-6 inches of manure or compost material. Both materials will give off heat as they compost, providing extra warmth to the melon plant roots. There are two main types of cucumbers, vining and bush. Bush cucumbers can be grown without supports and are popular for compact spaces and smaller gardens. The majority of cucumbers are vining cucumbers which need support for optimal growth. Use of a trellis, twining or fencing makes for an easy support structure. |
| Lettuce | 1-2 weeks | 1/4-1/2″ | 55-75F | Lettuce seeds are usually quite easy to sprout. Both the seeds and plants do best in slightly cooler weather, so plan on planting seeds when soil temperatures are below 70F. Sowing seeds. Lettuce is amenable to direct sowing in the ground, but take care to protect for garden pests which will quickly eat or destroy a fragile seedling. For sprouting in containers, choose small containers or flats and plant seeds 1/4-1/2″ deep in loose, well-draining soil. Soil temperature should be kept at 60-70F. Soil temperatures higher than 70F can inhibit germination and temperatures below 50F may do the same. If conditions are too warm but sprouting seeds is still desired, a trick is to put seeds in a wet paper towel, inside a ziplock bag. Put the bag into the refrigerator for 2-3 days then take the seeds out and sow. Properly sown seeds will generally germinate in 7-14 days. Transplant/thinning. For direct sown seeds, thin seedlings to 8-12″ apart, with rows up to 2-3′ apart, to give mature plants room to spread out. For container sown seeds, wait until a few true leaves have developed and carefully transplant to desired location. If sprouted indoors, make sure to harden off seedlings for 3-5 days prior to transplanting. To harden off, move seedlings to a filtered light location outdoors where they can slowly adapt to sunlight and outdoor conditions. Culture. Lettuce needs regular watering. Plants will grow best in loose, well-drained soils. Lettuce is very susceptible to nibbling by garden pests, particularly slugs and snails. Make sure to have proper slug barriers in place if slugs are a problem in your garden. Seeds can usually be stored for a minimum of three years. |
| Melons | 2-4 weeks | 1/2″ | 75-90F | Melon seeds are usually pretty easy to germinate, though an occasional variety may take longer than others. Melon seeds enjoy warm germination temperatures, so be sure to plant when adequate heat is available to warm the soil. Sowing seeds. Melon seeds should be started in small containers approximately one month prior to the desired outdoor planting date. Melon plants are highly frost sensitive so (in colder areas) be sure to time seed planting so transplanting seedlings takes place after the date of last frost. Sow seeds 1/2″ deep in small containers (up to 3″ pot size). Plant 1-3 seeds per container. Keep soil temperature between 75-90F. If soil temperature cools too much, seeds may germinate slowly or not germinate at all. Water regularly, when the soil surface begins to dry just a bit. Do not overwater seeds as perpetually dripping wet soil can promote the growth of fungus and bacteria which can kill the seed embryo. Most melon seeds germinate in 2-3 weeks, though some varieties can take slightly longer. Transplanting. Melons enjoy warm temperatures and regular watering. Make sure plants don’t dry out. It is common for leaves to droop a bit during warm summer days, so don’t worry so long as the soil still has moisture. The plants enjoy warm soil temperatures, preferably above 70F. If soil is not warm enough, several techniques can be tried. Covering the soil with black landscape fabric will raise soil temperatures. Cut a small hole for the melon plant. Another method is to amend the soil with 4-6 inches of manure or compost material. Both materials will give off heat as they compost, providing extra warmth to the melon plant roots. Most gardeners grow melons directly on the ground, but the plants can be grown on a trellis as well. Make sure to use sturdy support materials as melon plants can grow large and fruits may be heavy. Other Notes. Melon’s will produce both male and female flowers. Male flowers bloom first and will die back, so don’t fret if your plant starts blooming and doesn’t seem to immediately set fruit. It usually takes a few weeks for melons to begin producing female flowers, which can be differentiated from male flowers by a small swelling at their base. When watering, try to avoid watering the leaves. Damp leaves along with warm weather are a perfect environment for fungal growth, which can attack melon leaves. |
| Peppers | 2-6 weeks (C. annuum),2-10 weeks (C. chinense, C. frutescens, C. pubescens) | 1/4-1/2″ | 75-90F | Start seeds in small containers from 8-10 weeks prior to the last frost date. Plant seeds approximately 1/4-1/2″ deep in moist, well drained potting soil. Most standard soil mixes are suitable for pepper seeds. Soil temperature must be kept at 75-90F for proper germination. Cool soil, particularly at night can inhibit or significantly delay germination. Additionally, overly warm soils, well above 90F, can inhibit germination and provide ideal conditions for seed rot. To keep soil temperature warm, start seeds indoors, in a greenhouse and/or use a seed starting heat mat. Keep soil moderately moist, though not overly, dripping wet. Water soil when the soil surface just begins to dry. Allow proper air circulation for containers. Optionally, seeds can be dipped in a dilute hydrogen peroxide mix (1 tsp hydrogen perioxide per cup water) for one minute to disinfect seeds prior to planting. If your soil or seed sprouting setup is susceptible to mold growth this can be useful to kill mold spores. Once seedlings have sprouted, keep in small containers until a few sets of leaves have developed. Transplant to larger containers or outdoors. If transplanting outdoors, make sure to harden off seedlings by exposing them to only filtered sunlight for up to 1-2 weeks. Thin plants to 3-4 ft and rows to 6-10 ft. Estimated germination time under optimal conditions: 2-6 weeks |
| Radishes | 1-2 weeks | 1/4-1/2″ | 45-70F | Radishes are some of the easiest seeds to germinate. Plant directly in the ground, approximately 1/4″ deep, in loose, moist soil. Soil temperature should be above freezing, at least 45F or higher for germination. Germination may be slower in colder soils. Radishes are fairly cold hardy and can be planted as early as a week prior to the date of last frost. Germination time usually runs about 1-2 weeks under ideal conditions. Once seeds have sprouted, thin plants to 1-2″ apart and rows to 8-12″ apart. |
| Tomatoes | 1-4 weeks | 1/4-1/2″ | 70-85F | 1) Prepare for planting. Sprout tomato seeds in small containers, preferably 4″ or smaller. In-ground germination is not recommended. Use a standard potting mix that is well drained. Start seeds in containers approximately 8 weeks prior to the planned set-out date. Plants should ultimately be transplanted to the garden 1-2 weeks after the expected date of last frost. 2) Plant seeds. Plant seeds 1/4″ deep in the soil. Cover with soil and water carefully. Overwatering can cause fungal growth which leads to seed rot. Excess water can also bury seeds deep in the soil where they will not be able break the surface. Water when the soil surface just begins to dry. Multiple seeds can be planted in a single starter container, but should be thinned once seedlings appear so only a single plant remains. Seeds do not require light for germination but some light source should be provided for seedlings once they emerge from the soil. 3) Germination. Soil should be kept consistently warm, from 70-85F. Cool soils, below about 60-65F, even just at night, will significantly delay or inhibit germination. Additionally, overly warm soils, well above 90F, can inhibit germination and provide ideal conditions for seed rot. 4) Care of seedlings. Once a few true leaves have developed, seedlings should be slowly moved outside (if sprouted indoors) to ambient light. Care should be taken not to expose seedlings to direct, scorching sun so plants may need to be hardened off via slow sun exposure. Hardening off can be done using a shaded or filtered light location, as well as protection from strong winds, rain or low humidity. Hardening off time varies, but can take 5-10 days. 5) Planting out. Plant in the ground once danger of frost has past and daytime temperatures consistently reach 65F. Plants can be spaced as close as 24″ apart. Germination time: 1-3 weeks under ideal conditions. |
Vegetable Seeds (Brief Instructions)
| Species | Germination Time | Difficulty | Seed Depth | Soil Temp | Thin Plants to: | Rows Apart: | Notes |
| Beans (Phaseolus sp., Vicia sp, Vigna sp.) | 1-2 weeks | E | Warm (65-85F), wet soil is usually sufficient for fast germination. | ||||
| Bean, Lima (Phaseolus lunatus) | 1-2 weeks | E | 1/2-1″ | >55F | 6″ | Seeds can be planted directly in the ground after danger of frost has past. Or, plant indoors in small 3-6″ containers and transplant after 2-3 true leaves appear. Pole-type lima beans need up to 6′ support poles. Optionally, add soil inoculant to encourage maximum yields. Grow in full sun and in well-drained, slightly alkaline soil. | |
| Bitter Melon (Momordica species) | 2-6 weeks | E | Warm (75-85F), wet soil is usually sufficient for fast germination. Generally a bit slower to germinate than common melons. | ||||
| Broccoli | 1-2 weeks | E | Wet soil is usually sufficient for fast germination within days to a week or two. | ||||
| Brussels Sprouts | 1-2 weeks | E | Wet soil is usually sufficient for fast germination within days to a week or two. | ||||
| Cabbage | 1-2 weeks | E | Wet soil is usually sufficient for fast germination within days to a week or two. | ||||
| Carrot (Daucus carota) | 1-2 weeks | E | 1/4-1/2″ | >55F | 2″ | Warm (>55F), wet soil is usually sufficient for fast germination. Seeds can be directly sown in the ground once danger of frost has past. Plant at 1/4-1/2″. Germination generally takes from 1-4 weeks depending on soil temperature. Once seedlings have reached 2″ tall, thin to 1″ apart. Thin again to 2″ apart once seedlings reach 6″ tall. Use well drained, loose soil down to at least 6-7″. Hard and/or clay soils can result in poor growth. Optionally, use potassium rich soil amendments to promote sweet flavor. Avoid too much nitrogen based fertilizer as it can lead to fibrous roots. Plant seeds in a location receiving full sun for at least half the day. | |
| Cauliflower | 1-2 weeks | E | Wet soil is usually sufficient for fast germination within days to a week or two. | ||||
| Collards | 1-2 weeks | E | Wet soil is usually sufficient for fast germination within days to a week or two. | ||||
| Corn (Zea species) | 1-2 weeks | E | Warm (65-85F), wet soil is usually sufficient for fast germination. | ||||
| Cucumbers (Cucumis sp.) | 1-3 weeks | E | Warm (65-85F), wet soil is usually sufficient for fast germination. | ||||
| Gourds (Lagenaria species) | 2-6 weeks | E | Warm (75-85F), wet soil is usually sufficient for fast germination. Generally a bit slower to germinate than common melons. | ||||
| Lettuce (Lactuca sativa) | 1-2 weeks | E | 1/8-1/4″ | 55-75F | 8-12″ | Sow directly outside after danger of frost has past. Once seedlings emerge, thin to 8-12″ when 2-3 true leaves have formed. Alternatively, sow indoors in 2-4″ pots, of up to 3-6 seeds each. Transplant outdoors after 2 weeks, being careful to harden off plants. To harden off, place transplants in a shaded or filtered sun location for 2-3 days. Thin seedlings as above. Lettuce can be grown on and off throughout the year, but does best with air temperatures are in the 55-80F range. Keep plants out of direct sun in warmer areas and during the height of summer. | |
| Onion (Allium sp.) | 1-2 weeks | E | 1/4-1/2″ | 55-75F | 2-5″ | Sow seeds outdoors once soil temperatures reach 55F or warmer. Alternatively, sow indoors in small 3-6″ pots. Transplant outdoors once tops reach 3-4″ high. Thin bunching onion varieties to 2″ apart. Thin bulbous varieties to 5″ apart. Plant in well drained or loose soil. Avoid hard and/or clay soils which may inhibit proper growth. | |
| Pea (Pisum sativum) | 1-2 weeks | E | Wet soil is usually sufficient for fast germination. One of the easiest seeds to germinate. | ||||
| Peppers (Capsicum annuum) | 1 week- 2 months | E | 1/2″ | 75-85F | 12-18″ | 24-30″ | Variable. In warm soil (75F), many C. annuum peppers (the most common type) will germinate within a couple of weeks. Tepin and Pequin peppers are the trickiest, generally taking 3-6 months to germinate in warm soil. Do not use acidic soil. |
| Peppers (Capsicum baccatum) | 2 weeks- 2 months | E | 1/2″ | 75-85F | 12-18″ | 24-30″ | Variable. In warm soil (75F), many will germinate within 2-4 weeks. |
| Peppers (Capsicum chinense) | 3 weeks- 3 months | E-M | 1/2″ | 75-85F | 12-18″ | 24-30″ | Variable. Chinense species (e.g. Habanero’s) generally take longer to germinate than most common peppers. Germination is slower, but usually consistant after a few weeks. Keep soil warm to very warm (75-90F) for better germination. Do not use acidic soil. Some Chinense peppers, in particular Bhut Jolokia, Naga Morich and related peppers are very slow to germinate, averaging 1-4 months germination time. |
| Peppers Capsicum eximium) | 3-12 weeks | E-M | 1/2″ | 75-85F | 12-18″ | 24-30″ | Variable. Use warm (75-90F) soil. Seeds are typically slower than standard garden peppers to germinate and may take up to a few months. Warmth and humidity speeds germination. |
| Peppers (Capsicum frutescens) | 2 weeks- 2 months | E | 1/2″ | 75-85F | 12-18″ | 24-30″ | Variable. In warm soil (75F), many will germinate within 2-4 weeks. |
| Peppers (Capsicum pubescens) | 1-3 months | E | 1/2″ | 75-85F | 12-18″ | 24-30″ | Manzano type peppers usually take up to 2-3 months to germinate under ideal conditions. |
| Pumpkins (Cucurbita species) | 1-3 weeks | E | Warm (65-85F), wet soil is usually sufficient for fast germination. | ||||
| Radish | 1-2 weeks | E | Wet soil is usually sufficient for fast germination within days to a week or two. | ||||
| Spinach (Spinacia oleracea) | 1-2 weeks | E | Moderately warm (60-70F), wet soil is usually sufficient for fast germination. | ||||
| Squash (Cucurbita species) | 1-3 weeks | E | Warm (65-85F), wet soil is usually sufficient for fast germination. | ||||
| Tomatoes | 1-4 weeks | E | 1/8-1/2″ | 70-85F | 24″ | Seeds generally germinate fairly quickly in warm soil (>75F). In colder soil (<65F), they may be extremely slow to germinate or not germinate at all. Start seeds indoors, 5-7 weeks prior to outdoor planting date, in 3-6″ pots. Use a well drained, sterile, moist soil mix. Do not fertilize. Germination time is highly dependent on soil temperature and the most common reason for slow or no germination is cool or cold soil. Consistent, 24 hour bottom heat from a heating mat is recommended for best germination results. Transplant once danger of frost has past and daytime temperatures consistently reach 65F. Harden plants off for several days when moving outdoors by leaving seedlings in a sheltered, shady or filtered sun location. Set plants out 24″ apart. | |
| Turnip | 1-2 weeks | E | Wet soil is usually sufficient for fast germination within days to a week or two. |
Difficulty Key
Note that a number of seeds are rated at different difficulties, these are subjective ratings based on our and others experience germinating these seeds. Most people, following proper directions should be able to germinate easy and moderate seeds without much trouble. Recalcintrant seeds are generally easy to germinate—because many are in the process of germinating when they are harvested—but must be kept at proper conditions. Recalcitrant seeds tend to be highly picky about cool temperatures, low humidities and lack of water.
E = Easy (fast, requires little pretreament or experience with seeds, may germinate under widely variable conditions)
M = Moderate (slower to germinate (possibly a month or more), but still easy under typical conditions and requires minimal experience germinating seeds)
H = Hard (slow to germinate, requires proper conditions, may benefit from heating mat or controlled conditions; may require pretreatment or special treatment e.g. stratification)
VH = Very Hard (extremely slow or erratic to germinate, needs controlled conditions)