The weather outside is deceitful and sunny where it should be chilling and grey.

Pools of melted snow and patches of ice should be covering my garden. Instead, I am out pulling weeds... on New Year's Day! January is the month to be drooling over the seed catalogs flooding mailboxes. I am a seed-a-holic. What can I say? I can't say "no" to a pretty flower. Besides, I LOVE receiving treasures in the mail. A simple cardboard-colored envelope engulfs my summer dreams.

From zinnias to comoss, I have an array of seeds to start.

Though it’s not quite time to sow most of those magical seeds, it is time for sweet peas, on the other hand.

Why Sweet Peas Deserve a Spot in your Cut Flower Field

Sweet peas have an intoxicating scent that catapults us into the times of horse-drawn carriages and curtseying ladies. Their delicate petals bring such bliss as spring begins to awaken the earth from the dormancy of winter. It is fitting that the Victorian era's meaning is “bliss” or “delicate pleasure.” A handful of these dainty blooms in a vase will fill a home with refined beauty and a delicious fragrance.

Sweet peas are a huge crop for us and our customers. From selling plant starts to cut flowers, they are a novelty product that demands a higher price, but that does not sway folks! They were one of the biggest crops to carry us back when we only had about 1,500 square feet of growing space to work with.

Sweet peas are extraordinarily prolific and highly coveted in our market. Since sweet peas do not ship well and have a fleeting vase life, they are a tremendous variety to grow for the local cut flower grower.

Many older generations grew up with this flower in their grandparent’s gardens. Sweet peas are the flowers our customers have the most sentimental feelings about! Seeing them stick a bundle of these guys in their faces and inhale is lovely. Not sniff, inhale. It is as if they are inhaling and returning memories long forgotten until the fragrance of the sweet peas brings them all back in a rush. It is incredible!

As those spring nights transform into summer, I know our favorite thing to do is go out in the sweet pea patch and inhale that scent. We are watching hummingbird moths and bumbling bumble bees frantically working those flowers. Last year, we popped some shade cloth over the sweet peas when we got a crazy heat wave in May. Our girls took their tea party set and had tea with their dolls with the walls of the sweet peas enclosing them.

Not only are sweet peas significant to our customers, but they have also become significant to us. I can only imagine the memories rushing back for our girls when they are parents (or gasp! grandparents).

Before growing sweet peas, we must first order them, so let’s cover that first!

When and where to Order Sweet Pea Seeds

We try to have all our sweet peas on hand by fall, early winter at the latest.

We used to get a majority of our sweet pea seeds from Geoseed and Johnny Select Seed, but as we have gotten more into event florals, we have opted to purchase from smaller growers who have more muted or luxurious varieties of sweet peas. Floret when they offered them, Ardelia Farm who we are hoping will be back selling next season. I fell utterly in love with the non-tendril Alyosius Dickinson that I purchased from Ardelia in 2023, I was very much relieved to find Lunaseed Farm carrying them and other varieties that are recently difficult to come by. Baker Creek also carries some fun varieties o

We also save some of our own seed, which we’ll get to in a minute. If you are going to fall plant these guys, you should have them in hand by August or so (depending on your first frost date).

Which Sweet Pea Varieties Should I Grow for Cut Flowers?

Wait, what… it’s not as simple as just color and smelling pretty?!

Of course not.

There are varieties of sweet peas that bloom under shorter days and varieties that bloom under longer days:

Spencer
Early Multifloras

The early flowering variety that is my go-to is the elegance series. They thrive under shorter days and will keep producing gorgeous long stems if they are also planted in part shade. Their stems are incredibly long and often have five plus flowers on a single stem. I have found the burgundy to be exceptionally prolific and shoot long stems even in late June when grown in part shade. Along with elegance, we grow the mammoth series as well. They also bloom under the shorter days of spring. We find them to be a little more tolerant of heat in comparison to elegance and will happily grow in a our full sun.

Next we have the Spencer varieties. I love Spencer’s extra ruffly flower heads compared to the other two. Spencer’s are considered a summer blooming sweet pea since they need long day light hours. We squeeze these guys into our last two successions. Typically, our stems are much shorter since the summer heat is beginning to roll in which we get around by using some of the vine itself. We heavily rely on the Spencer’s for our June weddings with all those unique colors!

When to Start Sweet Peas

This answer is really going to rely heavily on your growing climate, hardiness zone and your growing operation. Sweet peas love to grow cold but not freezing.

We succession plant these guys. Fall we would start in mid-late summer and plant out mid to late September putting them under a double row tunnel when risk of frost arises. We do our main successions early winter (typically first week of January) then two more successions three weeks apart each. In our growing zone 6b, overwintering sweet peas can be a risk, therefore they need a good head start and protection. We played an experiment with an early winter planting recently. It frost nipped us in the butt. If you are aiming to plant out early, you will want to have them planted in fall so they can focus on that root development before the frosts of winter settle. In our experiment, we had them under a frost cloth tunnel but high winds ensued and we didn’t double back and check. Newly transplanted and they got hit pretty hard, minus a few survivors. Had we planted them out in fall they most likely would have survived the frost. Foliage would have died back but the plant itself would have survived and sent out new growth.

Sweet peas are actually rather hardy and a great spring to early summer flower.

How to Start Sweet Peas From Seed

You probably guessed it by the title of this section but sweet peas are typically propagated from seed. Incredibly easy actually. You can also propagate sweet peas from cuttings. This is something we are wanting to experiment with and will update once we do!

If you are ready to get some dirt under your fingernails, I’m ready to tell you how to start these little beauties. All you need is:

Quality sweet pea seeds

Your choice of substrate (we prefer a high quality potting soil)

Deep celled trays (such as root trainers), four inch pots or large soil blocker

Grow lights with a heat mat or full sun propagation house.

To learn more about seed starting be sure to check out our blog here.

Sweet peas are considered “heavy feeders,” meaning they love lots of good nutrients! Unlike some other flowers, sweet peas greatly benefit from the nutrients of a good potting soil versus just a peat moss seed start. Your potting soil should have plenty of perlite in it, for optimal drainage and healthy root growth. Sweet peas do not tolerate being soggy.

For better and quicker germination, soak the sweet peas in room temperature water for 8-12 hours prior to sowing. There are two schools of thought when it comes to whether or not to pre-soak sweet peas. Personally, I have tried soaking and not soaking. With the seeds we have, soaking has given us about 100% germination whereas not soaking I would say I have about 25% successfully germinate. In Roger Parson’s book “Sweet Peas an Essential Guide” he covers this a bit (link to purchase this book will be at the bottom of the post). Basically, it comes down to the source of the sweet pea.

Some sweet pea seed suppliers supply seeds with harder outer shells making soaking necessary and worthy. Other sweet pea seed suppliers supply seeds with a softer outer coating that pre-soaking would cause rot. We have found, soaking to be necessary for higher germination with seeds from these suppliers.

Now, there are tons of sweet pea growers who say soaking is not necessary and you can actually see a decrease in germination from soaking. They have solid reasons behind this. Outside of soaking seeds is an extra step to take in the process making it more time consuming, you good be inviting bacteria and fungi in by soaking that promote rot. Like I said, us personally, we’ve had better success pre-soaking. I definitely recommend experimenting and seeing what method you prefer!

We have awesome deep celled propagation trays we stumbled on from some fellow growing friends. This style of tray is commonly used for berry propagation.

Sweet pea seeds you can sow about twice their size in depth or about a quarter inch if you are looking for a faster germination.

How to Germinate Sweet Peas and Grow Starts

Sweet peas are a little more finicky than most other varieties when it comes to growing conditions. I think the biggest mistake we all make is actually growing them too warm.

For us, we soak the sweet peas, sow the seeds and boot them right out into the propagation house. It is in full sun but we vent it during the day and at night we minimally heat it to keep it from freezing. These guys really like to grow on the cooler side of about 55F. We have had the best success with this. Now on days we forget to vent the propagation house and it gets unseasonably warm the sweet peas have gotten sun scald and been pretty damaged in the past. We try to keep in the cooler areas of our tiny space.

Growing sweet peas can get kind of get tricky for the growers who are set up with heat mats and grow lights. Even the pros agree that this isn’t the best set up for sweet peas. The ambient temperature in the house is too warm then throw grow lights and heat mats on top of that, it becomes too warm for these spring beauties. This is when you get incredibly leggy, anemic looking plants. It also will make pinching these guys a necessary task that otherwise wouldn’t be had they been grown in their coveted cool temperatures. Even though our propagation house can get warm, by not having them on heat mats and watering them with our naturally cold well water they have done well (as long as we keep it from getting too hot!). They also handle cold nights really well. The result is a naturally branching plant with a healthy root system.

If your sweet peas are not naturally branching out or you want to take a cutting, when the sweet peas are four to six inches tall you want to pinch their stem down to the first or second set of leaves. Pinching will encourage them to branch out. Whether they are naturally branching or you pinched to encourage branching it will ensure a bushy plant with way more flowers to pick later on. Who can argue with having more gorgeous flowers at their disposal?

You want to avoid replanting the sweet peas multiple times. Starting the sweet peas in a four-inch pot, or another deep vessel, such as a deep celled propagation tray used for rooting berries or tree cuttings that are commonly used by nurseries, gives them some nice room. At least enough until they get nestled into the ground. Another bonus of growing them cold, it can buy you months before having to plant them out, all the while they heavily focus on growing a healthy root system. As much as you witness your sweet peas growing up, they are growing that much more down! We have found letting sweet peas get too root bound stunt them some or at the minimum set them back. If it comes down to bumping up a sweet pea, if you can’t plant out as intended, or letting them get root bound: bump them up!

How to plant Sweet Peas

The four to six weeks after sowing your sweet peas will fly by. March or April are typically good months to plant them out in the ground for most areas. The weather should be warming, the soil not a solid block of ice, but still nice and cool. Definitely make sure you harden these guys off appropriately, they can easily get sun scald which is lame. We typically prefer to plant them out minimally under a frost cloth to help them acclimate, if not a double low tunnel if its a harsher winter/spring.

We plant sweet peas eight inches apart and have two rows per bed of them. Sweet peas are a vine and will need to be trellised, which needs to be accounted for when planting.

Sweet peas love sun. Especially those mammoth and Spencer varieties. Be sure to plant them where they can get six to eight hours of sun for mammoth and twelve hours for Spencer, preferably morning sun and afternoon shade. Also, choose an area that they will be protected from winds. Properly trellising will also help them better withstand wind. If located in an area with ferocious winds, stems will be shorter. Many get around this by growing in high tunnels. We’re not that fancy…yet. We have had plenty of crop success growing them in the field though!

Mulching sweet pea plants can also help keep their feet cooler which will keep them into early summer. Personally, we like to grow calendula with the sweet peas to keep their feet cool since we are not fans of weed cloth. The shade of the sweet peas pushes the calendula to have longer stems. Win-win! If using weed cloth, I would really consider not using the black but opting for white to not warm up the soil too much.

We’ve been using chicken wire as a trellis but are looking at definitely upping our game and using hog wire fence for easier storage and setup. Also, unlike other vines sweet peas aren’t the best at clinging and holding themselves up. Wrapping baling twine around the whole system as the sweet peas grow taller will give that that extra support to climb up. A healthy happy sweet pea will tower up to nine feet! When they get to this height, we find we end up having to wrap bailing twine about three times as they grow.

Once again, sweet peas are heavy feeders, work some good compost into the growing site and fertilize with fish emulsion weekly. We’ve also learned the hard way that sweet peas are incredibly sensitive to sonic soil. Adding too much composted manure if you already have problematic soil can be detrimental to your crop. Definitely get a soil test in the fall! Sweet peas are one of the crops that greatly benefits from this. On our new property it is a definite work in progress to get these guys to grow willingly in our harsh Nevada soil. Even though we still had a lot of sweet peas to harvest, the beginning was rough and it took a ton of pampering!

If your sweet peas are too bushy and not flowering, cut back on the fish emulsion and spray with a fertilizer higher in phosphorous. Though sweet peas do not like to be soggy (so watch those moisture levels if you have clay soil) they are thirsty plants. Having them on drips has been a game changer in quality of plants. In our arid climate with suspicion of having some salt build up in our soil we also use yucca saponin to flush out the soil. We have found yucca saponin a must have in our arsenal of goodies in growing sweet peas. Since sweet peas are hungry, being able to flush out salt buildups from the fertilizers is important. On top of it, yucca is a magical liquid that helps with hydration and nutrient uptake both of which greatly helps sweet peas in our harsh arid climate. Link at bottom of post of what we use for hand flushing crops, once we get our fertigation system installed we’ll try some other bulk options to use and keep you updated!

For the maximum vase life, harvest the sweet peas when one to two blooms are open on the stem and put directly in clean water. I tend to skip the CVbN tablet for these guys. Bleach seems to quickly overpower their sweet smell. Super clean/sanitized bucket and frequent water changes is our post harvest care regimen. Change out water daily and re-cut stems every other day, this will give you about a good five days of vase life. The vine itself makes for great greenery and interest. Also, cutting some of the vine with the sweet pea stem will give an even longer vase life. When we are coming to the end of the sweet peas, I love to cut back and use as much of the foliage as possible as filler! I love to use sweet pea vines in bridal bouquets, their tendrils give such wisp and interest. Sweet peas and foliage do best when harvested in the morning but you will quickly find yourself harvesting morning and evening to keep up with the harvesting of these guys!

Sweet peas also don’t cross pollinate, yay! If you want to save seed, you can do that! Spacing out the varieties a little further apart so they don’t get entangled will help you to know which varieties of seeds you are saving. I have found the elegance and mammoth varieties to be great seed producers along with nimbus. The more specialty Spencer varieties such as Mollie Rilstone, I found were not great seed producers. This could be caused by a lot of different reasons but it can also simply be the habits of these varieties which would also explain their heavier price tag! The varieties that aren’t the best of seed producers is exactly the inspiration behind wanting to experiment with cutting propagating these guys.

Since sweet peas do not have incredibly long vase life, educating your customer about their ephemeral beauty is essential. They should understand and know what they are purchasing. They do make fantastic event florals and their tendrils are absolutely adorable in boutonnieres and corsages!

If you haven’t added sweet peas to your crop plan, it is time to change that tune! They are worth it! Give growing sweet peas a whirl, you won't regret it!

We are looking forward to helping you hand blooms soon.

- Jessica & Graham

wtf seed packets.JPG — Having a hard time deciding when to seed start?

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Sweet Peas