Join Our Sweet Pea Grow-Along: A Step-by-Step Guide to Starting and Growing Your Sweet Peas

In many parts of the country there is still time to start and plant out your sweet peas for a lovely display of blooms in June and July, so I thought it would be helpful to show step by step how I start and grow my sweet pea vines and you can take part if you want to.

What is a "grow along"?

Blog and social media posts where we share our sweet pea growing experiences - just check out this blog post every week(ish) and I'll update you with how I'm doing. You can post photos in Instagram and/or Facebook tagged with #sweetpeagrowalong to show everyone how you are getting on. Or you can just take part by watching and growing at home.

How to take part

You'll need some sweet pea seed, some pots, plant labels and a good potting soil. I've chosen Apricot Queen, Spanish Dancer and Clotted Cream to grow together as I think their colors compliment each other. I've also decided that I am going to plant these in a large pot (when large enough) and provide them with some canes for support.

Week 1

I've taken a 4" pot and filled it with my favorite, high quality potting soil. Then I added a label so that I know what variety sweet pea this is. Then I poked 4 small holes towards the corner of the pot, placed my seed and covered it over. I'm going to set these on a sunny windowsill until I see shoots appearing. You can check out my detailed instructions on growing sweet peas.

Week 2

After about 4-5 days, my sweet pea seeds germinated and I can see the tiny little seedlings beginning to emerge (it's always an exciting moment!). Sweet peas germinate best at temperatures from 55-65°F. Once you see the seedlings emerge, you need to move your pots to a place where they will receive plenty of light and remain protected from birds, mice etc. An unheated greenhouse or cold frame works fine.

Week 3

You can see the quick growth that is happening after just another week! The first leaves are almost open. Some of the seeds I planted are just emerging. Not all sweet pea varieties will germinate at the same time: Apricot Queen and Clotted Cream are all germinated and at the stage shown in this week's image, but Spanish Dancer is a little behind with some of the seeds only just showing signs of germination - they will all catch up to each other though. My seedlings are a little more 'leggy' than I would like, telling me that they are not getting enough light. That is partly the fault of grey days we have been having and my greenhouse glass that needs a good wash!

Week 4

My little sweet pea seedlings now have 2 - 3 sets of leaves and are starting to grow tendrils which they use to pull themselves up onto a trellis or other support. Some of the seedlings are starting to develop side shoots which is just what I want as that means they will become a bushier plant with more flowers. The seedlings are still in the 4 inch pots and starting to deplete the nutrients from the potting soil, so this week I am starting to feed them. I simply give them a diluted fish emulsion and feed it to them after they have already been watered. Next week I will pinch them to encourage the development of more side shoots.

Week 5

I find that you don't really need to pinch sweet peas because they usually start to bush out by themselves. Meaning that they start to develop side shoots from the main stem. However, you can snip or 'pinch' off the top growth. Wait until your sweet pea plant have 2-3 sets of leaves. My little seedling has 4 sets of leaves, so just going to take a pair of scissors and cut off the main stem above the third set of leaves.

Week 6-7

5-6 weeks after germination, my little sweet pea seedlings are ready to be planted outside.

My seedlings were grown in 4 inch pots and the roots have filled out nicely after about 6 weeks of growth.

Here's a late seedling - this one is way behind and looks like it germinated about 2 weeks ago. Discard any seedlings that look smaller and weaker than the rest.

I'm planting this batch of sweet pea seedlings in a pot. It must be about 24 inches deep. I will be adding support next week.

Week 10

There wasn't much to see for the last few weeks - my sweet pea plants have just been growing happily in their pot. But now that they are starting to get taller, I have put some willow canes in the pot which I will use for support once the plants need it. You can use bamboo, trellis or anything else you think would work.

Sweet Pea Planting Reminders

Knowing when to plant sweet peas will greatly improve your success with these enchanting and fragrant flowers. Fill out our sweet pea planting reminder form and we will notify you when to plant sweet peas for the area you live in.