The top reasons why there are no flowers on sweet peas are too much shade, too much water, planting too late in the season and too much nitrogen. Plant sweet pea seeds in the sunniest spot possible in early Fall and add a flower promoting fertilizer in winter. Follow these easy steps for bright, beautiful sweet pea flowers.
Sweet pea flower problems and solutions
|No flowers on sweet peas
|Solutions for more flowers
|Too much shade
|Plant seeds straight into your garden in the sunniest spot possible. More sun=more flowers.
|Too much waterOnly add water to your seeds once they have sprouted through the ground and only water when the top soil is dry 2 inches below the surface.
|Planting too late in the season
|Plant seeds in early Fall to give them enough time to establish and grow flowers.
|Poor quality seeds
|Use seeds that are in date and have been kept fresh and dry. Discard any damaged seeds.
|Not enough time
|Wait until late winter before you give up on flowers on sweet peas.
|Not enough potassium
|Add a fruit promoting fertilizer that has a high potassium to nitrogen ratio to encourage flowers.
|Too much nitrogen
|Stop adding nitrogen rich liquid fertilizer like fish fertilizer and switch to a fruit promoting fertilizer.
|Seeds were covered in mulch
|Do not lay mulch near sweet pea seeds and rake back any that may have blow over the seeds.
No flowers on sweet peas – Problems
Too much shade
Sweet peas need a full sun position so they grow to their full height of 8 feet and grow bright flowers. Too much shade will stop sweet peas from growing to their full size and growing flowers. They will stay small and although they may grow leaves, will not grow flowers.
Too much water
Too much water can rot sweet pea roots and stems before they have time to produce flowers. Stems will turn yellow and then brown, bending and breaking before they grow flowers. They can be attacked by pests because their stems and leaves are not strong.
Too much water can stop your peas from growing into a large, healthy plant before they grow flowers.
Planting too late
Planting sweet peas too late in the season will not give them enough time to grow to their full size and grow flowers. Sweet peas will need be planted in early fall so they have time to grow and establish ready to grow flowers in late winter.
Poor quality seeds
Sweet pea seeds that are out of date, damaged or have got wet will not grow well. Choose fresh, dry seeds and check the date before purchasing from a nursery. Any leftover seeds from the year before can be stored in a glass mason jar with a piece of paper towel to absorb extra moisture.
Not enough time
Sweet peas can take as long as 3-4 months before they will flower so you may need to wait until late winter before you see any flowers. More time might be all that is needed to get your sweet peas growing more flowers.
Not enough Potassium
Sweet peas will need an increase in potassium to encourage them to grow more flowers. Sweet peas that are getting lots of nitrogen and not enough potassium they will grow lots of leaves and stems but not flowers.
Too much nitrogen
Too much nitrogen will encourage lots of leaf and stem growth for your sweet peas so it is great in the beginning. Too much nitrogen near the end of the season when you want your sweet peas to grow flowers can stop them from blooming.
The easy solution is to stop adding nitrogen fertilizer after planting. Your peas will naturally use up the nitrogen in the soil as they grow and the ratio of potassium to nitrogen will increase, promoting more flowers.
Easy steps to promote flowers after planting sweet peas
If you already have your sweet peas planted in your garden and they are not yet growing flowers, here are some easy solutions to get 3x more flowers on your plants.
Stop adding nitrogen
Don’t add any more pelleted chicken manure or liquid fertilizer like fish emulsion. This will allow the plant to use up the nitrogen in the soil. It will also be used up by soil microbes and worms reducing the levels gradually in the soil.
Add a flower promoting fertilizer
To tip the balance of nutrients so there is more potassium in the soil to promote more flowers, add a flower and fruit promoting fertilizer. This will have a higher ratio of potassium and encourage your sweet peas to sprout flowers.
Water and mulch
After adding the flower promoting fertilizer to sweet peas, water it in and add a covering of sugar cane or straw mulch. This will set your sweet peas up to absorb the potassium-based fertilizer and start flowering.
Tips for more flowers for next season’s sweet peas
Here are my top tips for more flowers on sweet peas when you plant them in the next year.
Plant in the sunniest spot in your garden
Choose the sunniest position you can find to plant sweet peas in your garden. The more sun they get, the more flowers they will grow.
Give your sweet peas support
Sweet peas will need a support to grow up to reach as high as possible and grow lots of flowers. They will grow tendrils which will grab onto a trellis or stake and grow up to reach towards the sun.
Plant early in the season
Plant sweet pea seeds early in Fall to give them plenty of time to grow before they will reach up and flower. They need to grow to a larger size before they will flower well. Give them the time they need to reach full size by planting early.
Buy good quality seeds
Choose good quality sweet pea seeds that are still in date, have been kept dry and are not damaged. This will give your peas the best chance to grow well, healthy and grow lots of flowers.
No flowers on sweet peas – Summary
There are simple steps to growing as many flowers on your sweet peas as possible. Sweet peas grow best in the sunniest spot possible so remember this when you plant the seeds out in your garden.
Plant pea seeds straight into garden soil as they do not like to be moved once they have started growing. This is the easiest way to avoid transplant shock which can slow your sweet pea growth.
I am an accredited practicing dietitian, experienced gardener and a dedicated cook. I love writing and sharing my experience so you can learn from my successes and mistakes.