Harvesting castor bean seeds from your garden is easy. In this post, I’ll give you step-by-step instructions for how to collect castor bean seeds from your plants, and I’ll also show you how to store castor seeds.
In some areas of the world, castor bean plants are invasive. But here in Minnesota, they make beautiful and unique tropical plants that die back every fall (funny how that works).
I love growing castor bean plants in my tropical garden, and I always get tons of compliments on them!
I especially love this red castor bean variety that I have been growing in my tropical garden for a few years now.
Red castor bean plant growing in my garden
Table of Contents
Castor Bean Seeds Harvesting
I first received my red castor bean seeds in a trade, and have been collecting the seeds from my garden every year since. It’s very easy to collect castor plant seeds and save them for planting next year.
Castor bean flowers are insignificant, but they form gorgeous seed pods that look like flower puffs at first.
Red castor bean seed pods start out as bright red puff balls, which really add to the beauty of this plant.
The seeds will form inside of these red puff balls, so be sure to leave them on the plant if you want to collect castor bean seeds.
Red castor bean seed pods
When To Harvest Castor Bean Seeds
The seed pods will start to fade and eventually turn brown. Allow castor bean pods to dry on the plant so that the seeds have plenty of time to mature.
Eventually, the seed pods will split open, which is a sure sign that it’s time to start collecting castor seeds.
Don’t worry about collecting castor bean seeds before frost, I usually don’t get around to it until after a hard freeze, and I haven’t had problems with seed viability.
Castor bean seed pods ready to harvest
What Does A Castor Bean Seed Look Like
Castor bean seeds are oval shaped and have a nub on one end of the seed. They are pretty large, and hard to miss – larger and rounder than edible bean seeds.
Truth be told, castor seeds actually kinda remind me of an engorged wood tick (disgusting, I know!).
Castor bean seeds and pods
How To Collect Castor Bean Seeds
To collect castor bean seeds, first clip the dried seed pods from the plant. Castor seed pods are very prickly, I recommend using gloves to handle them.
You can store the seeds right in the pod, or remove the seeds from the pods before storing them.
To collect castor plant seeds, break open the seed pods. There are three castor seeds per seed pod. Sometimes not all the seeds in the pod are large enough to keep.
Discard any castor bean pods or seeds that are small, they won’t be mature enough to germinate.
Collecting castor bean seed pods from my garden
How To Store Castor Bean Seeds
Allow your castor seeds to dry completely before storing the seeds. Ideally, the seeds should be stored in a dark, dry place until spring.
Once they’re dry, you can store your seeds in a paper bag or small plastic containers (like these film canisters).
If you wan to share them with friends, then these small envelopes are perfect, or you can get customized seed envelopes, or make your own DIY seed envelopes.
I store my seed collection in a plastic shoe box, but if you like to organize yours, then a Seed Keeper would be perfect!
It’s important to note that all parts of the castor bean plant are poisonous, so be sure to keep castor bean seeds and seed pods out of reach of children and pets at all times.
Harvesting castor bean seeds
How Long Does It Take To Harvest Castor Beans?
You may need to wait as long as 170 days for your castor plants to become fully mature before you can harvest the seeds.
They need a long, hot growing season. So if you live in a cold climate like I do, make sure you give them plenty of sun.
Where To Find Castor Bean Seeds For Sale
It may be difficult to find castor beans for sale, depending on where you live. But most garden centers should sell the seeds from mid-winter through spring.
Of course, you can always buy castor bean seeds online. Here is the type I grow… red castor bean seeds.
Collecting castor bean seeds from the garden is fun and easy! It’s a great way to grow your favorite plant year after year, and share the seeds with friends (just be sure to let them know that both the seeds and plants are poisonous).
Now that you know how to collect castor bean seeds, learn how to grow castor seeds next!
If you’re new to gardening and want to learn how to grow seeds indoors, then my Starting Seeds Indoors eBook is just what you need. It’s a quick-start guide for beginners to get started learning how to grow their own seeds. Download your copy today!
More Posts About Saving Seeds
- Collecting and Sowing Spider Plant Seeds
- How To Harvest & Collect Seeds From Your Garden
- How To Collect Lavender Seeds From Your Garden
- How To Harvest Butterfly Weed Seeds
Share your tips for how to collect castor bean seeds in the comments section below.
Jamie says
I have caster growing and we want to harvest seeds but ours are not forming seed heads yet and it’s almost September. We live over in Wisconsin.
Any idea
Amy Andrychowicz says
Unfortunately there’s nothing you can do to force castor bean plants to set seed. If they don’t form any seed pods, then they may be getting too much shade. Next year make sure you give them full sun all day.
Clayton Ross says
Castor Bean, Ricinus communis, Ricin is Latin for tick
Cindy mitchell says
I grew my first castor bean tree this year. I was told to harvest seeds right after the first frost – which I did. But i think it was too early. The seed pods are still green. I laid them on cardboard in my dry basement but now somehave mold on them. Is it too late to save any?
Amy Andrychowicz says
Oh bummer. Yes, castor bean seed pods should be brown and dried out before harvesting them. It sounds like yours may not be mature enough. I would take them out of the pods and let them dry out that way. You never know, maybe you’ll get lucky and a few will germinate. Good luck!
Carol says
How long do you dry the seeds before storing. How do you know when they are dry enough?
Amy Andrychowicz says
I let my castor seeds dry for at least month or more before storing them. If you keep them in a paper bag, then you don’t have to worry about them being dry enough before storing them.
Ken says
Amy, you are incorrect stating that freezing weather will kill castor bean seeds. I’ve kept mine in the freezer for over 10 years and they grow just fine.
Amy Andrychowicz says
Interesting. It must have to get below a certain temperature to kill castor seeds, because they definitely don’t survive the winter outside here in MN – but it can get down to -20F+ below zero, which is much colder than a freezer. Thanks for sharing your experience!
Shirley says
My plant This year has like a flower or more like a mushy cauliflower growing underneath the sea pods why is this ? did some of the pods turned to dust ? The rest of the pods are bright red nowhere near ready to come off the plant yet.
Amy Andrychowicz says
It sounds to me like the flowers weren’t pollinated on your castor plant, and that’s why no seeds formed and the pods turned to mush. I would just prune it off.
Joey Phillips says
What if they self sow but don’t pop up until you’ve got the rest of the garden.thriving and growinng well, I’ve got a couple that’s sprouted up right in with my watermelons will this poison. What’s around.the caster bean plant?
Amy Andrychowicz says
No, the poison doesn’t leach into the soil, and is not absorbed by other plants. However, they do grow very large, and will compete with your veggies for water and light. So, if I were you, I would move the castor bean seedlings somewhere else so they have plenty of room to grow, and won’t crowd out your vegetables.
Jodi says
Hi Amy. I’m also in Minnesota. I purchased some castor seeds to plant. Do you just put them in the ground, or do you need to start them inside first? I read that they need a lot of heat to germinate. Thanks!
Amy Andrychowicz says
Since our growing season is so short here in MN, and the ground is so cold in spring, it’s best to start castor seeds indoors. Here’s how to do it step by step for the best results.
Brenda says
Hi Amy. I picked the prickly balls off the plant on the fall. Now when I get the seed out, the seed doesn’t feel really hard. Should the seed be hard?
Amy Andrychowicz says
Castor seeds should be pretty hard after harvesting them, if you did it at the right time. The prickly balls (seed pods) should be brown, dried out and brittle before collecting the seeds. If the seed pods are still red or soft, the seeds probably aren’t mature enough to be viable. I would either plant some to see if they grow, or perform a viability test on them.
Rodger Stevens says
Hello Amy, I grew some castor plants at one end of my vegetable garden and collected some seeds when they were ready, but I didn’t collect them all. Will my vegetable garden be safe when I start working the soil for the next planting season ?
Amy Andrychowicz says
If you live somewhere cold, the freezing weather will kill the remaining castor seeds, so you won’t have to worry about them reseeding. But, if you live in a warm climate, then I would remove them or they could self sow.
shashere michael says
hi, actually I don’t really know much about castor beans, but a friend of mine enlightened me of it. I do see it all the time, it grows and become a tree in my area.
how can the oil be produce?
Amy Andrychowicz says
Castor oil is pressed from the seeds. I’m not sure if this is something you’d be able to do at home or not, I’ve never tried it myself.
Linda says
How do I dispose of the castor bean plant at the end of the year. If I put it in my garbage it will go to the landfill. Is that ok since the plant and seeds are so poisonous?
Amy Andrychowicz says
I put my castor bean plant into my compost bin, or into the yard waste bin for composting.
Angela Holt says
If its poisonous is it a good idea for a compost ben? Expecially if your compost is being put on a vegetable garden….seems like it wouldn’t be ideal.
Amy Andrychowicz says
The castor bean poison doesn’t survive composting. So, it will be gone once the plant is done decomposing.