Aptly named, Mammoth sweet peas have extra-large flowers with lengthy stems—perfect for cutting! The subtle, sweet scent is delightful, too. Developed in the 1980s from Early Multiflora Gigantea, a Spencer-type sweet pea, this variety boasts drought and heat resistance, which results in a longer season of blooms. Attracts pollinators. Deer resistant. Caution: Most parts of this plant are toxic if ingested.
~2.0 g
(~19 seeds)
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- Variety Info
- Sowing Info
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Variety Info
Family: Fabaceae
Type: Sweet Pea (Learn more)
Native: Italy
Hardiness: Frost-tolerant annual
Exposure: Full Sun to Part Shade
Bloom Period: Spring to Summer
Plant Dimensions: 5'–6'
Variety Info: 1''–2" flowers with moderate scent in shades of rose, blue, salmon, scarlet, white, lavender, and burgundy.
Attributes: Attracts Pollinators, Drought Tolerant, Heat Tolerant, Frost Tolerant
Sowing Info
When to Sow Outside: RECOMMENDED. Cold Climates: 4 to 6 weeks before your average last frost date. Mild Climates: Late fall to early winter for spring bloom. Ideal soil temperature is 55°–65°F.
When to Start Inside: 4 to 6 weeks before your average last frost date.
Days to Emerge: 10–21 Days
Seed Depth: 1"
Seed Spacing: A group of 3 seeds every 6"
Thinning: When 3" tall thin to 1 every 6"
Your hardiness zone is
- Rhonda K.Verified BuyerRated 5 out of 5 stars4/19/26Sowed as instructed!
Beautiful blooms just not in every color .
Which best describes you as a gardener? IntermediateBIBotanical Interests4/19/26Hey Rhonda,
Thank you so much for this fantastic 5-star review of the Mammoth Blend Sweet Pea Seeds! It's wonderful to hear that you followed the sowing instructions and got those beautiful blooms - that's exactly what we love to see!
I totally understand the mixed feelings about not getting every single color in the blend. Sweet pea blends can sometimes be a bit unpredictable in terms of which colors decide to show up strongest in any given growing season. Sometimes certain colors in the mix are just more dominant or quicker to establish than others, even though they're all in there.
It sounds like you did everything right with your sowing technique though, and those beautiful blooms you're enjoying are proof of your great gardening skills! Sweet peas are such rewarding flowers to grow when they take off like yours have.
Thanks for sharing your experience with the Mammoth Blend - it really helps other gardeners know what to expect!
Keep on growing 🌻️
- Magda C.Verified BuyerRated 4 out of 5 stars4/10/26Somewhat disappointed
I planted both packages of seeds & had very few come up. I presoaked them as instructions indicated. Attaching a picture of what terminated. Expected more of the seeds to take hold because of the better quality of t he seeds.
Which best describes you as a gardener? IntermediateBIBotanical Interests4/12/26Hey Magda,
Thanks so much for taking the time to share your experience with the Mammoth Blend Sweet Pea Seeds—we really appreciate your honest feedback, and it sounds like you followed all the right steps with the presoaking.
We're sorry to hear that you didn't see the germination rate you were expecting from both packages. Sweet pea germination can sometimes be influenced by a few different factors beyond the seed quality—things like soil temperature, moisture levels, planting depth, and even the age of the soil can all play a role in how well seeds take hold.
That said, we definitely want to make sure you get the results you're looking for. We'd love to take a closer look at your situation and see how we can help ensure your next planting experience goes more smoothly.
We really value customers like you who give us detailed feedback—it helps us continue to improve. Thanks again for sharing your experience with us.
Keep on growing 🌻
- BriannaVerified BuyerRated 5 out of 5 stars8/26/25Easy to germinate, didn’t work out for me
These germinated well, were beautiful in bloom, but unfortunately didn’t work out for where I had them. I have a very dry and hot south facing garden and these would have been my best option for a sweat pea cultivar. Too hot though so I’m bummed I didn’t get to see them at their best.
Which best describes you as a gardener? IntermediateBIBotanical Interests8/26/25Hey Brianna,
Thank you so much for sharing your experience with our Mammoth Blend Sweet Pea Seeds! We're so glad to hear they germinated well for you and gave you beautiful blooms - that's wonderful! We totally understand the challenge with that hot, dry, south-facing spot though. Sweet peas can definitely be tricky in those intense heat conditions, even the more heat-tolerant varieties. It sounds like you really know your garden conditions well and were thoughtful about your variety choice. We appreciate you taking the time to share this helpful insight about growing conditions - it's really valuable for other gardeners who might be dealing with similar hot, dry spots! Keep on growing 🌻️
- Dorian D C.Verified BuyerRated 5 out of 5 stars2/12/255 Stars
my daughter told me about your company .. she only buys seeds from you! so I thought I'd give it a shot ..
- Jeanne T.Verified BuyerRated 5 out of 5 stars1/21/255 Stars
The sweet peas are sprouted and look very healthy.