Hey garden lovers! It’s that time of year when our beloved sweet peas start winding down their spectacular show. If you’re wondering what to do next I’ve got you covered with this comprehensive guide. As an experienced gardener who’s grown these beauties for years I’m excited to share all my tips and tricks!
Understanding When Sweet Peas Are Done Flowering
Before we dive in, let’s quickly identify when sweet peas are truly finished flowering:
- Fewer new flower buds forming
- Existing blooms looking tired and faded
- More seed pods appearing
- Yellowing leaves, especially at the plant base
- Stems becoming woody and less flexible
1. Keep Those Blooms Coming (If Possible!)
Daily Deadheading
Regular deadheading is the most important thing you can do to make sweet pea season last longer. Here’s what I do:
- Cut flowers every 1-2 days
- Remove spent blooms before they form seed pods
- Snip stems just above a leaf node
- Use clean, sharp scissors or pruning shears
If you miss some and seed pods appear, don’t worry—just get rid of them right away to get the plant’s energy back on flower production.
2. Feeding and Watering
Sweet peas are hungry plants! To keep them going:
- Water consistently – about 1-2 inches per week
- Feed every 2-3 weeks with liquid fertilizer
- Focus on phosphorus and potassium rather than nitrogen
- Apply seaweed or comfrey tea for an extra boost
3. Maintenance Tasks
Tidying Up
- Remove tendrils that curl around flower stems
- Cut off old, matte-looking leaves
- Clear away any fallen debris
- Keep air circulating between plants
Support Structures
- Add extra support if needed for new growth
- Secure loose stems to prevent tangling
- Check ties aren’t too tight
4. Saving Seeds for Next Year
If you wanna grow the same varieties next season
-
Choose the best pods:
- Wait until they turn brown and brittle
- Select from healthy, vigorous plants
- Pick larger pods for better seeds
-
Harvesting steps:
- Collect on a dry day
- Store in paper bags while drying
- Clean seeds and dry for 2-3 days
- Store in cool, dry place
5. End-of-Season Cleanup
When flowering is truly finished:
For Annual Sweet Peas:
- Cut vines down to ground level
- Remove all support structures
- Clean and store supports for next year
- Add healthy plant material to compost
For Perennial Types:
- Cut back by 2/3
- Leave roots intact
- Apply winter mulch
- Mark plant location
6. Preparing for Next Season
Don’t forget about next year! Here’s what I do:
- Add compost to replenish soil
- Consider planting cover crops
- Plan crop rotation
- Order seeds early for best selection
Common Problems to Watch For
Keep an eye out for these issues as plants finish flowering:
- Powdery mildew
- Aphids
- Spider mites
- Root rot
My Top Tips for Success
- Start deadheading early and often
- Don’t skimp on plant food
- Keep air flowing between plants
- Stay on top of watering
- Save seeds from your best performers
FAQ
Q: Can I just pull everything out when flowering stops?
A: You could, but I recommend gradual removal if saving seeds or trying for late blooms.
Q: Should I cut back perennial sweet peas?
A: Yes! Cut them back by about 2/3 but leave the roots intact for next year.
Q: How long can I extend the flowering season?
A: With proper care, you might get an extra 4-6 weeks of blooms, depending on weather.
Have any questions about managing your sweet peas? Drop them in the comments below – I’d love to help!
Would you like me to explain any part of this guide in more detail?
The Biggest Mistake Growers Make with Sweet Peas:
Now that I have a better understanding of how-to grow sweet peas, I can look back at my failed attempts and see so clearly what I was doing wrong.
You wouldn’t believe how easy it is to grow sweet peas from seeds. They just need to be grown at a different time than the cut flowers most of us are used to growing.
Allow me to explain…
The biggest mistake I made when trying to grow sweet peas was growing them too warm.
Like many beginner flower farmers, I assumed that all flowers prefer warmth—that seedlings should be pampered, kept cozy on heat mats, and protected from cold at all costs.
But sweet peas don’t just tolerate cold—they thrive in it.
Looking back, I can see where I went wrong:
- Putting seeds on a heat mat is not a good idea because sweet peas grow best when it is cool.
- Putting off transplanting until after the last frost (it was too late by then)
- Not giving them enough time to get set up before summer got hot
I thought I was being kind to my plants by shielding them from the cold—but in reality, I was holding them back.
So, how do you actually grow strong, healthy sweet peas? Let’s dive in…
When to Sow Sweet Pea Seeds:
If you live in a mild area, you might be able to plant your sweet peas in the fall and let them grow through the winter.
In Zone 5b where I grow, it’s simply too cold for sweet peas to survive our entire winter season- so I start my seeds in the very early spring.
Keep in mind that sweet peas grow best with the following temperatures:
- 50-55 degrees Fahrenheit for germination
- It needs to be 35 to 50 degrees Fahrenheit to grow. Don’t worry if the temperature drops; sweet peas can handle being in the 20s!
- 45-68 degrees Fahrenheit for flowering.
What this means is that for most cold-climate growers, you’re going to want to sow your seeds in containers in late January thru early March and transplant those seedlings out in your garden as soon as the soil can be worked.
I often like to take my cues from Mother Nature and as soon as I see the daffodils start to peak above the soil- that’s when I know it’s time to plant my sweet peas outside.
Just to give you an idea of the timeline I use; last year I sowed my sweet pea seeds in trays indoors on February 13th and I planted them outside on April 10.