Growing seeds sometimes seems like a cut and dry experience. This unfortunately is not true. A lot goes into growing seeds. Gardeners must know how many seeds per hole, soil conditions, and water requirements to plant seeds. Regardless of the type of seeds being grown, all seeds require a few common ground elements for successful growth. These elements are:
- Warm soil
- Light
- Water
- A growing container
- Quality soil that has nutrients for seedlings
It is ideal to start seedlings in a container and not directly in the ground outdoors unless they are root vegetables. Once the seedlings reach a point of maturity they can be transplanted into a garden or planter box outside once the weather is sufficient for their successful growth.
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What does Germination rate mean?
A germination rate is based on how many plants sprout per 100 seeds. If 70 plants sprout from 100 planted seeds the germination rate will be 70%.
When purchasing seeds the information on germination is located on the packaging. Germination information will include the percentage of seeds that should sprout and the amount of days it will take for the seeds to sprout as well as how many seeds per hole to plant.
How many seeds should you plant per hole?
The amount of seeds planted per hole is dependent upon the type of seeds being planted. Larger seeds such as zucchini, melon, pumpkin, sunflowers or pickles should all only contain one seed per hole. Smaller seeds like carrots, beets, lettuce and kale can have 2 to 3 seeds per hole. If all seeds planted per hole sprout the seedlings can be thinned out later. The following seeds are commonly found in most gardens and planter boxes.
Broccoli
How Deep To Plant Broccoli Seeds
Broccoli seeds can be planted 2 to 3 per hole. They should be planted 1/2 to 3/4 of an inch deep in soil.
When to Transplant Broccoli
Once the broccoli plants have sprouted and are 4 to 6 weeks old with no less than 4 leafs present; they can be transplanted in a garden. They should be planted as deep as the container they are growing in and 12 to 20 inches apart in the garden or planter box.
How To Increase Germination For Broccoli
Broccoli seeds can be soaked for one or two days prior to planting. This can increase the change for a higher percentage of germination.
Additional Facts About Broccoli Seeds
Broccoli and cabbage are both known for consuming large amount of nutrients from soil. They should never be planted near one another and soil needs to be amended before planting each year.
Radish
How Deep To Plant Radish Seeds
Radish seeds should be planted in groups of 2 to 3 per hole. The hole should be no more than 1/2 an inch in depth. Some gardeners will even say they only require a dusting of dirt to cover the seeds.
When To Transplant Radish
Radish seeds will sprout fairly quickly; often within 5 to 7 days. It is not recommended to transplant radishes but if they must be moved it should be done while they are young. Gardeners should dig down about 4 inches to ensure they don’t damage the root system.
How To Increase Germination For Radish
Soak seeds in water for 15 minutes and then spread them out on a moist paper towel. Place paper towel in window sill. Keep paper towel moist but not soaked. Seeds will sprout within 48 hours.
Additional Facts About Radish Seeds
Radishes grow rapidly and are typically ready to harvest within 25 days. They can be grown in containers both inside and outside.
Carrots
How Deep To Plant Carrot Seeds
Plant 4 seeds 1/4 of an inch in depth in a shallow container.
When To Transplant Carrots
Carrots should typically be started in a garden. If they are started in a sowing kit then they should be transplanted when they are only 7-14 days old.
How To Increase Germination For Carrots
Seeds take 2 to 3 weeks to germinate. To enhance germination the top layer of soil should be kept moist
Additional Facts About Carrot Seeds
Carrot seeds are slow to germinate and will not sprout at all if the temperature is too cold.
Beets
How Deep To Plant Beet Seeds
Plant 1 to 2 seeds in a 1/4 to 1/2 inch deep hole. Beets should be planted 3 to 4 inches apart from one another.
When To Transplant Beets
Beets can be grown directly in the soil or in larger containers but it is not recommended that they are transplanted.
How To Increase Germination For Beets
A combination of peat moss and garden soil will increase the germination for beets. They should also be sown every 10 days to increase chances of variety and size.
Additional Facts About Beet Seeds
Beet seeds germinate in 5 to 12 days and the root size is controlled by the spacing of the seeds.
Lettuce
How Deep To Plant Lettuce Seeds
Lettuce seeds are small and only require a 1/4 to 1/2 inch deep hole. 3 seeds can be planted per hole.
When To Transplant Lettuce
Once lettuce has 4 to 6 leaves it can be transplanted into a garden or planter box.
How To Increase Germination For Lettuce
Soak lettuce seeds for at least 16 hours prior to planting to increase germination
Tomatoes
How Deep To Plant Tomato Seeds
Tomato seeds should be planted in sufficient soil 1/8 an inch deep
When To Transplant Tomatoes
Tomato seedlings can be transplanted when it is above 50 degrees consistently outdoors and the plants are at least 3 inches tall.
How To Increase Germination For Tomatoes
Increase germination of tomato seeds by spritzing with water twice daily and keeping under a warm light.
Basil
How Deep To Plant Basil Seeds
Plant 2-3 seeds in a 1/4 inch deep hole. A start kit or container is ideal
When To Transplant Basil
Transplant basil when it is at least 3 inches tall with 2 leafs
How To Increase Germination For Basil
Moisten seeds for at least 12 hours before planting to increase germination
Additional Facts About Basil Seeds
Basil plants are sensitive to cold weather and frost. They do not regrow annually and must be replanted each year.
Pea
How Deep To Plant Pea Seeds
peas should be planted 1 seed per 1 inch deep hole and spaced out 3 inches between.
When To Transplant Peas
Once pea sprouts reach 3 to 4 inches in height they can be transplanted to a garden
How To Increase Germination For Peas
Soak over night and lay out on a damp paper towel the day prior to planting indoors
Additional Facts About Pea Seeds
Peas are typically ready to harvest 60-70 days after planting
Onions
How Deep To Plant Onion Seeds
Plant 5 to 8 onion seeds 1 inch deep per hole
When To Transplant Onion
Transplant onion sprouts 8 to 10 weeks after sprouting
How To Increase Germination For Onion
Bottom heat and fluorescent plant lights help increase onion seed germination.
Additional Facts About Onion Seeds
Onions require great drainage, ample sunlight and good quality soil.
Bean
How Deep To Plant Bean Seeds
At least 2 bean seeds must be planted in each 1 inch deep hole
When To Transplant Beans
Once the bean seedling has 3 or more leafs it can safely be transplanted
How To Increase Germination For Beans
Soaking bean seeds for a few hours before planting can increase germination
Additional Facts About Bean Seeds
Beans are typically harvested 50-60 days after seeds sprout
Zucchini
How Deep To Plant Zucchini Seeds
Zucchini seeds should be planted 1 per hole at 1/2 inch depth and 4 inches apart
When To Transplant Zucchini
Zucchini seedlings can be transplanted to a garden once they have 2 leaves
How To Increase Germination For Zucchini
Soak in warm water for 48 hours prior to planting to increase germination
Additional Facts About Zucchini Seeds
Thin out too many plants because zucchini tends to over-crowd
Thyme
How Deep To Plant Thyme Seeds
Plant 2 to 3 seeds in a 1 inch deep hole
When To Transplant Thyme
Transplant thyme seedlings when the plant has at least 4 leaves
How To Increase Germination For Thyme
Thyme seeds are slow to germinate and can take 2 to 3 weeks
Additional Facts About Thyme Seeds
Thyme typically comes back every year once it is initially planted in the soil
Cucumber
How Deep To Plant Cucumber Seeds
Plant one cucumber seed 1 inch deep into soil. Plant seeds 18 or more inches apart
When To Transplant Cucumber
Transplant cucumber seedlings once they have 2 to 4 leaves
How To Increase Germination For Cucumber
Fold seeds into a moist paper towel and place in a air tight container in a window sill. After 4 days they will sprout and be ready to plant.
Cabbage
How Deep To Plant Cabbage Seeds
Plant 2 seeds in a 1/2 inch deep hole in a starter kit. If planting directly in ground space out 2 feet between each hole.
When To Transplant Cabbage
Transplant about 6 weeks after sowing
How To Increase Germination For Cabbage
Cabbage seeds germinate faster in soil over 70 degrees
Cauliflower
How Deep To Plant Cauliflower Seeds
Plant 2 to 3 seeds per each 1/2 inch deep hole
When To Transplant Cauliflower
Transplant when each seedling has at least 2 leaves
How To Increase Germination For Cauliflower
Plant at least 3 seeds per hole for a better chance of growth.
Additional Facts About Cauliflower Seeds
Not every cauliflower seed will sprout. They have a 70% germination rate.
Sun flowers
How Deep To Plant Sunflower Seeds
Plant 1 sunflower seed 1/2 an inch deep and at least 6 inches away from other sunflower seeds.
When To Transplant Sunflowers
Transplant sunflower seedlings when they are at least 4 inches in height
How To Increase Germination For Sunflowers
Direct sunlight speeds up germination. Water away from plant area as water is taken in by the root system.
Corn
How Deep To Plant Corn Seeds
Plant 2 to 3 corn seeds in each 1/2 inch deep hole. Plants should be 12-15 inches apart.
When To Transplant Corn
Corn seedlings should be transplanted outdoors once they are 1 to 2 weeks old
How To Increase Germination For Corn
Corn seeds germinate best in room temperatures of 50-59 degrees
Peppers
How Deep To Plant Pepper Seeds
Plant 1 pepper seed in a 1/2 inch deep hole
When To Transplant Peppers
Transplant pepper seedlings when they are more than 6 inches tall
How To Increase Germination For Peppers
Place seeds in a damp paper towel and then place inside a zippered bag. Check daily for sprouts.
Watermelon
How Deep To Plant Watermelon Seeds
Create a 12 inch deep hill, plant 1 seed 1 inch deep into each hill. Hills should be spaced out 6 feet apart.
When To Transplant Watermelons
Transplant watermelons when they have at least 2 leaves
How To Increase Germination For Watermelons
Plant in high quality dirt hills when the weather is consistently 70 degrees or higher
Kale
How Deep To Plant Kale Seeds
Plant 2 kale seeds 1/4 inch deep.
When To Transplant Kale
Transplant kale seedlings when they are 9 inches high and have at least 4 leaves.
How To Increase Germination For Kale
Mulch with straw around Kale plants to keep the soil moist.
Additional Facts About Kale Seeds
Kale is a cooler weather plant and thrives in the spring and fall months. It can also be grown year round in a container near a window.
Spinach
How Deep To Plant Spinach Seeds
Plant 2 to 3 seeds in 1/2 inch of shallow soil.
When To Transplant Spinach
Spinach is best grown in a garden or container. If transplanting do so when 2 leaves have formed.
How To Increase Germination For Spinach
Prime seeds in warm water for 24 hours and then place in a paper towel for 2 to 3 days before planting.
Squash
How Deep To Plant Squash Seeds
Plant 1 seed per hole at 1/2 inch depth.
When To Transplant Squash
Transplant squash when each plant has 2 leaves.
How To Increase Germination For Squash
Increase germination by starting in a damp paper towel for 2 days prior to planting.
Okra
How Deep To Plant Okra Seeds
Plant 2 to 3 okra seeds in a 1/4 inch deep hole.
When To Transplant Okra
Okra should be grown directly in a garden because it has a high failure rate for transplant.
How To Increase Germination For Okra
Soak okra seeds over night in warm water to speed up germination process
Additional Facts About Okra Seeds
Once mature, okra plants can produce okra for 10 to 12 weeks.
Pumpkins
How Deep To Plant Pumpkins Seeds
Plant 1 seed per hole. Hole should be 1 inch deep. Space out 6 feet apart from other pumpkin seeds.
When To Transplant Pumpkins
Transplant pumpkins once they have 2 leaves.
How To Increase Germination For Pumpkins
Hasten germination by placing pumpkin seeds on a moist paper towel and keeping it damp for 2 days.
Additional Facts About Pumpkin Seeds
Pumpkins take up 6 feet of growth per plant. Plant where they will not choke out other plants.
Melons
How Deep To Plant Melon Seeds
Plant 1 seed per 1 inch deep hole and space holes 18 inches apart.
When To Transplant Melons
Melon seedlings are typically ready to transplant into a garden 2 weeks after sowing.
How To Increase Germination For Melons
Fertilize soil before planting to boost germination
How to increase germination?
One of the most important processes of gardening is the germination of your plants. So how do you increase your seedlings germination so you can have a lush garden?
Firstly, soak your seeds before planting them. Seeds require quite a bit of moisture to grow into sprouts, this is part of why it takes so long for them to germinate. When you soak your seeds, you can open them up to germinating faster.
The second tip is to start with your seeds indoors. You can set aside a place that is safe from storms or drastic weather changes to increase your plant’s chances of germination by simply buying a seed tray that you can place inside your home by a window seal.
The third tip is mandatory if you want your plants to thrive and that is to keep your seeds watered correctly. Of course, it is good to keep in mind that you can overwater them. Making sure your soil is moist and not drenched will increase the chances of your seeds germinating.
Read our article about How Often Should I Water Seedlings? | Watering Guide
How deep to plant your seeds?
The typical rule for planting seeds into the ground is to plant them at a depth of two or three times their width. This is a rule of thumb because it’s better to plant seeds too shallow than too deep. Otherwise, they wouldn’t peak through the soil.
How far to space seeds apart?
The closest you can space seeds apart is 2 inches and the furthest you should space is around one plant per 4 square feet. However, spacing seeds apart can vary depending on the plant, so its 2 inches to four square feet and anywhere inbetween.
For example, large plants such as zuchinnis and squash will be spaces a lot more than carrots or beets. The larger the plant the more spacing required, typically this information is found on the seed packaging if available.
Final Thoughts
Jamie is the founder of The Backyard Pros. When he was 15 years old he started working at a garden centre helping people buy plants, gardening products, and lawn care products. He has real estate experience and he is a home owner. Jamie loves backyard projects, refinishing furniture, and enjoys sharing his knowledge online.