How to Grow Peas Q +A

We often quote our book “Food Grown Right, In Your Backyard” and say that fresh snap peas are a reason unto themselves to have your own garden. I’ve never eaten a pea that has tasted as good as the ones I grow in my home garden, and I want you to have the same experience.

Read this article to find the answers to your pea-growing questions and get set up for success!

Pea Q & A

Before we start, please note:

1. This post addresses snap and shelling peas (aka. edible peas.) Sweet peas, which are grown for their flower and are not edible, are an entirely different beast.

2. Edible peas fall into two general categories. Shelling peas are typically grown to maturity on the vine and then the shell is removed before eating. Snap peas are harvested before they are fully mature on the vine and usually eaten whole with the shell on.

Q: How close together can you seed/transplant snap, snow, and shelling peas? 
A: Pea plants should be spaced 1-2 inches apart. Peas can grow well when spaced close together, so don’t be afraid to pack them in a little. If you do plant them this close together, space rows several feet apart. Over-planting reduces air circulation and makes your plants more susceptible to mildew. 

Q: When can you plant peas? 
A: Snap peas are ready to harvest around 60 days after they’re planted, and are a cool-weather crop. Your planting date will depend on your growing region. Peas grow well when temperatures are between 55-65 degrees F, and they don’t germinate or grow well when temperatures get above 75°F. The climatic limitations make peas a great crop for spring or fall planting. In Seattle, we plant our spring peas from mid-February through late-March.

You can also plant peas for fall harvest by seeding them in late summer. We’ve found that this technique can be tricky for a few reasons:

1. Mid-July tends to be when gardens are the fullest, so it can be difficult to find space to plant peas for fall. 

2. You have to plant them in the height of summer to give them enough time to mature before the growing season comes to a close. Often, summer temperatures are just too warm for peas to germinate and perform well. We’ve had some success sowing varieties with a slightly shorter lifespan (maturing in about 50 days) in the fall. Sugar Ann and Tom Thumb are some good fall planting options. These varieties tend to also have a shorter growth habit than longer season varieties.

Q: Should you direct-seed or transplant peas? 
A: Both work well, but we prefer to transplant.

We tend to transplant peas because birds and slugs love newly buried pea seeds and tiny pea sprouts. We find that transplanted peas are less likely to be eaten by hungry critters.

If you want to direct seed, just keep a close eye on your planting! Direct-seeded peas usually germinate within a week. If you notice that your new sprouts are getting chomped by slugs or birds, just reseed as soon as possible. If your seed doesn’t germinate at all, or germination is spotty, gently dig around your seeded row and see if the seed is still there. Crows and other birds love eating them whole. You can fill in a spotty row with new seeds and the later-planted ones often catch up with the original row.  

If you are having pest issues, sprinkle your planting with iron phosphate (to keep the slugs at bay) and drape some bird netting over your bed. After your peas have grown to about 3 inches in height, gently remove the bird netting. Be sure not to break any of the growing tips on your pea plants as you do this. If you forget to remove your bird netting, your plants will start to get caught in the netting and you’ll have created a new issue for yourself to negotiate. 🙂

Transplant your seedlings into the garden when they are between 2-4” tall. Any taller and they become fragile enough to break during planting (they also tend to grab onto each other in the tray, making it harder to separate them). They do grow quickly, so if you end up with taller transplants than intended, just be very careful when transplanting, taking the time to gently separate them when removing from the tray.

A note on timing: If sown early enough (in the PNW, sometime in March), direct seeded peas often catch up with transplanted peas once it comes time to start producing.

Q: What is inoculant, and should I use it on my peas?
A: In the garden, inoculants are bacteria or fungi that are intentionally added to the soil or seed of a crop to promote a healthier plant.  A healthy and active microbial population is essential to the success of your crops.  By adding certain microbes directly to the soil, you can help create an especially robust soil ecosystem in your garden.  

The most common garden inoculant is a bacteria known as Rhizobium (often sold simply as “garden inoculant” which is added to the seeds of legume crops at planting time.  The most common garden legumes are peas and beans, which are supported by the same strain of bacteria (as are lentils).  Additional strains exist for soybeans, peanuts and other outlying food crops.  

The bacteria forms a symbiotic relationship with the root nodules of legume crops which allows the plants to absorb nitrogen from the air, use it for growth and deposit it into the soil.  Legume plants and crops are unique in this ability, and it is usually referred to as “nitrogen fixation”.  Even though the air we breathe is 78% nitrogen (N2), plants can’t use it in this form.  It must be converted into ammonium nitrogen (NH4+) or nitrate nitrogen (NO3-) before plants can absorb it and use it for growth.  Rhizobium allow the legumes to convert N2 from the air into NH4.  This is helpful for the legume crop, but also leaves behind a store of NH4 in the soil for the next plants in the garden to use.  

Inoculant is inexpensive and the application is easy.  There are numerous techniques to mix the inoculant powder with the seeds, but the most effective is to create a “slurry”.  It is best to inoculate the seeds just prior to planting, so separate out the seeds you need for the planting, pour them into a plastic or ceramic container, sprinkle inoculant onto the seeds, and add a few drops of water until the powder sticks to the seeds and coats them lightly.  The exact proportion of powder is not crucial, a little bit goes a long way and chances are that you are much more likely to over inoculate then under, and that’s okay, you can’t really add too much.  The only downside is wasting the inoculant.  

Q: What is the best way to trellis peas?
A: There are a few great ways to support your pea plants.

First, a few notes about how peas grow:

1. Peas are a vining plant that holds onto your trellis with tendrils. However, their tendrils are relatively weak compared to those of other crops like pole beans. This means that they need extra training to keep them attached to any trellis. Without ongoing training, they are likely to pull off of your trellis under their own weight. This usually snaps the top of the vines and reduces your overall harvest.

2. Remember that pea vines are very delicate, which means that you don’t want to try and move or adjust them very much once they are growing. So your training technique needs to be very delicate to help keep your vines intact.

3. Different types of peas have different mature heights. For example, Oregon Giant snow peas only grow about 4’ tall, but Sugar Snap peas can grow up to 7’ (or more). The height of your trellis should accommodate the variety you’re planting. This is one of the many reasons we designed the Freyr Trellis, it can adjust in both height and length, making it easy to grow different crops and different varieties of crops. Fortunately, the tops of any pea plant can be trimmed off. We often trim our peas 3-6” above the top of our trellis to make sure the vines don’t fall over and snap. In fact, trimming your tops once your plants have reached their mature height can actually encourage your plants to set more blossoms on the lower sections, making harvesting easier.

We’ve been growing peas for decades and have tried every trellising option:

1. Bamboo tipi: You can create a simple tipi structure and train your peas up the poles. To keep the vines attached to the trellis, make sure to wrap the entire planting with twine every week as they grow.

2. Pea netting: Setting up a net gives your peas a great surface to grow up. Their tendrils will wrap around the net and this technique tends to make harvesting and training easier than growing on a tipi. However, since the plants are heavy and fragile, it’s still a good idea to add extra pieces of horizontal twine to help hold the peas against the net as they grow. This is very easy and only takes a few minutes a week. It can give you a perfect planting of peas.

3. Horizontal strings: Similar to using a pea net, we also love to just use horizontal strings to wrap around our pea planting. The technique is simple, just wrap a piece of twine across both the front and back of the planting. Repeat this every 6-12 inches as they grow. To add extra support, you can tie the front and back strings together (or use a trellis clip to hold them together) check out the video below to see how we do this on our Freyr trellis.

Q: Peas only take 58 days to mature, so if I plant them now (in early March), I can pull them and plant my tomatoes in their place in early May, right?
A: Probably not.

This is a common point of confusion and it comes down to two things:

1. Not all growing days are created equal. Early spring days and early fall days may technically be part of your growing season, but plants are going to grow much more slowly in these cooler and shorter days than they will during the long, warm days of summer. This means that even though peas need to be started while the soil temperature is still cool, they won’t get going until things warm up a bit.

2. Fruiting crops have an extended harvest period. Peas are a fruiting crop, which generally means that they will produce many fruits over an extended period of time, as opposed to a head of lettuce, which is one done and ready to harvest for a short period of time. Your peas might START producing after 58 days in the ground, but that doesn’t mean you want to pick the first 10 peas and call it a season. You want those plants to continue producing as long as possible. After all, you’ve waited 58 days and probably dedicated some valuable garden space to the plants. 

We tend to remove March-planted peas from gardens in mid-July. This is closer to 110-120 days after planting. At this point in the season the heat is starting to get to the peas and they start to get powdery mildew. By this point we’ve harvested pounds and pounds of fruit off of the hard-working plants over an extended period of time.

Since we generally plant tomatoes in mid-May, there are actually 2 months of overlap when both peas and tomatoes are in the garden.

In short, 58 days is the minimum amount of time it’ll take for your plants to begin producing, but you’ll usually need at least another 30-60 days to capture your full harvest. Therefore, it’s best to replace a spring planting of peas with a shorter season crop like cucumbers or climbing zucchini, if you wanted to utilize vertical growing space; or salad greens, beets, carrots, or fall brassicas such as broccoli and kale if not.

Q: How do I harvest peas?
A: Peas are very easy to harvest, simply pick them right off the vines. A few tips to get the most out of your plants:

1. Pick snap peas early and often. Snap peas typically taste best when picked small so they are still tender. Also, picking your fruit every few days will encourage more fruit production, so they more you harvest the more you get to harvest later!

2. Wait to harvest shelling peas until the pods have swollen and the peas inside are visible. Since shelling peas are grown only for the seeds inside (and not the pod), you want to wait until these are sized up which makes them easier to harvest and makes sure that you actually have something worth picking. If you pick too early, the seeds inside will just be micro-sized!

3. As mentioned above, consider trimming the top of your vines when they reach the top of your trellis. This will prevent the tops from snapping and encourage additional blossom (and therefore fruit) production on the lower parts of the vines.

More questions about growing peas?

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