Herbs & Edibles

 

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What areyou growing here, Tom?

Yeah, it's interesting, isn't it?

So things like this squash here...

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Welcome to "Gardening with Steil."

Growing herbs at home is both tasty and beautiful. Herbs are plants with many uses, including culinary, medicinal, and aromatic. They are easy to grow, have few disease or insect issues, only need moderate levels of fertility, and require little space. Culinary herbs are some of the most rewarding edible plants to grow. They add distinctive flavors to all types of food. And while dried herbs are wonderful, fresh herbs from the garden are even better. Not to mention that herbs are attractive ornamental plants, and many are great for pollinators. Herb gardens are great additions to an Iowa landscape. We had a chance to see an amazing example of an herb garden at the Dubuque Arboretum and Botanical Gardens. There, we had a chance to learn more about some of the best herbs to grow in Iowa.

Jenna, thank you for the invitation to come out and vist here today. This is such a special place.

Yes, it is.

Tell me more about the Dubuque Arboretum and Botanical Gardens.

Yeah, the Dubuque Arboretum and Botanical Gardens was established in 1980. We have over 300 volunteers who take care of and maintain our grounds and only a couple staff members. So, it is truly amazing that our volunteers that come out here and have taken care of 56 acres and have turned it into an arboretum and botanical gardens for all to enjoy.

You have a lot of different garden spaces here. We're standing in a Japanese garden.

Yes.

What other spaces are here at the gardens?

We have over 60 gardens, a prairie garden. We have a conifer collection. We have rose garden, perennial gardens. You name it, we most likely have it. We even have an English garden as well.  And I'm particularly interested in seeing the herb garden.

I know you have a few volunteers. A few volunteers are here. Please lead the way, Shirley.

It looks amazing.

Yeah.

Just beautiful.

What do you do to kind of take care of all of this?

Well, the herb garden here in the arboretum is adopted by the Dubuque Herb Society. There's many members, and we all have a certain garden that we take care of. Most of the herbs and the plants here require at least six hours of sunlight, so that dedinitely they get that.

What are some of your favorite herbs?

You know, basil …

Mm-hmm.

...is a real good herb to start with. It smells great. Um, you can also just have it in containers outside. You can bring it inside in the winter. And you just keep, you know, cutting back. Also oregano, rosemary and thyme.

Those are just some four basic herbs that you can put them in containers, have them in your home in the wintertime, and, you know, cut them back and have fresh herbs anytime.

Steil: I know there's lots more to see. We have some edible flowers here.

Yes, kind of one of my favorite that’s pretty easy to grow and pretty versatile is a nasturtium. You can get red, yellow, you can get variegated leaves. You can get different things with it. But one thing about the nasturtiums, they’re great for a salad. Even the leaves and the flower, they have more of a kind of peppery taste.

And that’s just one of many flowers in here. You have daylilies and roses, pot marigols, or calendula. Just a wonderful variety of a really fun group of plans.

They are.

Fran, you’ve joined me here with the fragrant herbs. Tell me a little bit more about some of these neat plants.

Some of them are scents that people love, but insects hate, and sometimes vice versa. This one is southernwood. It’s in the Artemisia family. And if you rub that and then smell it …

Some people love that and some people hate it.

Oh!

That’s really nice.

It’s kind of a – almost like a spicy kind of scent.

Yes.

This is an ancient herb. Crusaders carried it to ward off the plague. It’s a flea repellent.

Okay.

And it was the flea that carried the plague.

Sure.

These are scented geraniums. Unlike your zonal geranium, they're grown for their leaves. And that's a rose-scented geranium.

Yeah.

And they're so pungent.

Yes.

Mm-hmm.

So they can be used in potpourri. But you can also -- they could be in the culinary garden. You can line a cake pan with these leaves, put in your batter, and the flavor infuses into the cake that you're making.

That's a cool thing to do.

It's a real Victorian thing, so it's kind of fun.

And this is a very Victorian plant.

That's right. That's right. You got some classic herbs here too, like lavender and rose.

Right.

This is a rugosa rose. And we make jelly out of the petals.

Is this lemon verbena? What is this?

It is. So it's not a native. We have to winter it over inside or buy it every year.

It reminds me a little bit of Pledge, but much nicer scent.

[ Laughs ]

Much nicer.

Right.

Steil: Thank you for sharing so much knowledge with me today.

It's been wonderful.

You shouldn't walk in here if you don't want to get a lot of information, because we really like to talk about these herbs and their history and how they're used. So this was the perfect opportunity.

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What a beautiful garden!

One of the best things about growing herbs is they're not only beautiful but useful. There are many ways to harvest and preserve herbs for use in cooking or for things like potpourri. Starting with harvest, you'll want to harvest plants when they're large enough, usually about midsummer in Iowa, and then again near the end of the season.

For annuals, we're gonna use something like a scissors to cut them off, and we're going to cut back to about four to six inches to allow new regrowth.

For perennials, we're not gonna cut back quite so aggressively. We're only gonna remove about a third or less of the plant at any given time when we're harvesting.

And of course the scissors can work for that. But also something like a pruners can work for perennials, especially if they have thicker stems. Once we have all of our stems, we can look at preserving them.

Of course, it's great to use them fresh, but if we can save them, we can use them later on in the season.

One of the simplest ways to preserve herbs is to air-dry them. So bundling them together and using things like string or twine. Rubber bands work really well too. As these herbs dry, the stems are going to shrink a little bit, so we want to make sure that they're bound nice and tightly in a bundle so that when they dry, they don't fall apart and fall down.

If we don't have a great place to hang herbs in bundles like this, we can also use something like an old window screen to dry them. And this also works really well for those herbs that don't have a lot of long stems, like thyme, or even sometimes oregano.

We're going to spread these out in a single layer on this screen. We can put spacers in between and stack screens up, as long as we have good airflow.

We want to put our herbs, whether they're hanging or on a screen, in a warm, dry location, about 70 to 80 degrees, and usually in about two to four weeks they're dry enough to store.

Another way that we can preserve herbs apart from air-drying is heat-drying. Just don't do it too hot or fast, or you'll destroy the flavor of the herbs. You can use an oven. Simply set the oven for 180 degrees, arrange your herbs on a cookie sheet, and put them in there for about three to four hours with the door slightly ajar. You can also use a food dehydrator, and all you have to do is follow the instructions that  come with that appliance.

Whether you're air-drying or heat-drying, once the herbs are fully dry, we want to store them in an airtight container and keep them away from heat and light.

One of the nice things we can do apart from drying herbs is we can also freeze them. And this works really well for certain herbs like parsley, chives, or basil. Simply puree the herbs with a little bit of water and freeze them in ice cube trays. Then we can store those little ice cubes full of herbs in a plastic bag in the freezer and pop them into sauces or soups whenever we want to add that flavor.

Another fun way to preserve herbs is with vinegars or oils. Oils like this are great for cooking with. Vinegars can be really nice for salad dressings, where you're going to simply steep the herbs in the oil or vinegar for about four to six weeks.

Just as there are many ways to preserve and use herbs, there are also many ways to grow them. For example, basil, cilantro, and parsley are great herbs to grow indoors in a container situated in front of a bright window. They can also be grown indoors under grow lights, allowing you to harvest fresh herbs even in the middle of winter.

Some herbs and other edible plants can be grown without any soil at all.

Cindy Haynes had a chance to visit Morningside College in Sioux City, where students are learning all about growing in hydroponic systems.

Haynes: Oh, fish. I see big fish.

Paulsen: You bet.

This is our aquaponics room, where we're actually using fish and fish waste to actually provide the nutrients for all of our raft system here in our aquaponics lab.

I love the lettuce. How old is this lettuce?

Well, this lettuce is probably about three weeks old, and most of our lettuce takes about 52 days to get from seed to full-grown lettuce plant, like you see over on the other side.

This is nice, and this is just a floating system that's recycling from your tilapia, right?

It is, actually. In the tilapia tank, the waste from that are basically taking the ammonia and turning it into nitrates in our bacteria tank here. And the plants are using that nitrate and cleaning the water and sending it back to the fish, so it's a really good system.

It is a good system when it works.

Yes, when it works.

This is a little tricky sometimes. It's a little tricky in a production system like this. We have insect issues we have to deal with, typically some disease problems. But it's a lot of fun and it provides some really great opportunities for our students to problem-solve and figure out, how do we handle a production system like this?

Yeah, you're checking on this daily to make sure it's in the right levels of everything.

Absolutely.

And it looks like it's working.

It's so far so good.

Let me show you another style of production that takes up a lot less floor space.

Oh, wow!

This is vertical gardening.

It is, it is.

Welcome to our tower farm.

I like it. And growing a lot of different types of lettuce.

Absolutely, a lot of different types of lettuce, lettuce that actually is used on our campus. Our students learn the production processes, the harvesting processes, the food safety processes. They'll harvest in class at 8:00 in the morning, and that lettuce will be on the salad bar by 11:00.

Wonderful! How great for them to know that they have grown their lunch. I love this. And it's a lot of different types at different stages, so you're harvesting how often?

Every week.

Every week. So yep, we're on a very, very strict schedule. So the students are planting, transplanting, and harvesting every week. I see them in different stages.

I also noticed some other things over here that aren't lettuce.

There are. And I'd love to show you that project.

Okay, let's go take a look.

What are you growing here, Tom?

Yeah, it's interesting, isn't it?

Yeah, it's not lettuce.

No, it's not lettuce. This is an African celery.

Nice.

The seeds came actually from the Democratic Republic of the Congo. And then this is an African amaranth. The amaranth project was brought to us by Dr. Annie Kinwa-Muzinga, who's a member of our faculty. She's an agribusiness professor, and we have quite a Congolese community here in the Sioux City area that really has asked for some traditional food staples. This came out of an entrepreneurship class project. So students have actually taken the produce to an African grocery store in Sioux City and worked with the customers to get that product.

I love it that you're growing things that students can use.

I love that you're growing things that the community can use, and the students are learning so much about this entire process.

Absolutely.

All in one or two greenhouses.

Yes.

And having a lot of fun.

Yeah! Good job.

Yeah.

Thanks a lot.

Thank you.

Hydroponic systems like the one Cindy just visited may look complicated, but you can actually set up

a system of your own at home.

Herbs like basil grow very well in these soilless systems, as do other edible plants like lettuce and  tomatoes. To start, all hydroponic systems have some of the same basic components. One of those components is a support system. They're usually in a net pot, and it can be some kind of inert substance like perlite, which is very easy to find at garden centers or stores. You can also use something like coconut coir, which is also relatively easy to find. There are other substrates that are really nice for hydroponic systems that are often sold specifically for them, things like clay pebbles, or this rockwool.

When we grow things without soil in water, we still have to provide oxygen for the roots. And there's two ways that we can do this. We can do it as a passive way. Another way that we can introduce air to the system or air to the water is with something like an air stone.

So, much like an aquarium, that bubbler thing that you can put in an aquarium, you can add that to a hydroponic system to introduce air. We can also use recirculating water to help aerate that solution.

One of the easiest forms to do at home is deep water culture. And this is where basically you're going to suspend your plants in a bucket of water. And you can find kits that do this, or you can make one at home just like this one with a five-gallon bucket. I've just drilled some holes in the top of this that fit my net pots, and I will fill this bucket with water and allow water up to the bottom of the net pot and allow those roots to grow down into the solution, and making sure that I keep that air gap for, um, proper aeration of the plants.

Other things we need, first thing to think about is the nutrient solution. There are lots of little recipes online that you can use to do this, but you can also just -- and this is a great place to start if you're getting started -- just use a premade solution. They make different mixes for different types of plants.

So there might be one that works really well for tomatoes and another one that works really well for herbs. You're going to mix these things up just as it's directed on the container, and that's what you'll use for creating that nutrient solution.

The ideal pH for a hydroponic system is somewhere between 5.4 and 7. And so we can use pH testing strips like these to test the water to make sure that it's in that acceptable range. And if it's not in that range, we can add things like baking soda to raise up the pH or citric acid to lower it.

But the best place, especially for beginners, is to just simply buy a premade solution that's specifically made for adjusting pH in hydroponic systems. Just be sure, no matter what you're doing in this hydroponic system, since we're growing edible plants in it, we need to make sure that all the components, from the buckets to the chemicals we're using, are food safe.

We want to test the water every few weeks to be sure that it stays in that same pH range.

Once we have our solution in place, it's the right pH and the right alkalinity, we can put it in our deep water culture. We're going to fill this bucket up to the bottom of the net pots. We're going to let those plants grow into it. The plants that we use can really be anything. Herbs do really well in hydroponic systems.

Certain plants definitely respond to this kind of system better than others. You're going to start those plants as seedlings, just as you would any other seedling that you might put out in the garden. Then you can rinse off the roots, and the best way to rinse off the roots is just swish them around in a container of water, and then plant them in whatever substrate you're choosing to use. That seedling that's placed in that pot will then grow down into the solution, and over time the solution will drop down. But that's okay, because we want at least one half of our roots submerged and the other half out of the solution. Bacteria and fungus grow really well in this solution. And so over time, especially after about two months, it's a good idea to swap out the solution for fresh new stuff. Dump out the old solution, but don't put it down the drain. Put it in your garden. It's full of nutrients and fertilizer. Then clean the container really well with soap and water, rinse it, and fill with a new nutrient solution so that only about half of the roots are covered.

While herbs can be potentially grown in a wide range of conditions, including hydroponic systems like this one, they do have a couple of important growing requirements. Herbs grow best in full sun. That's four to six hours of direct sunlight a day. And they need well-drained soil. The deep, fertile soils of Iowa don't always provide the best drainage for herbs. The Loess Hills, found along the western border of Iowa, however, do provide great, well-drained soil for herbs like lavender to grow well.

Cindy had a chance to visit the Loess Hills Lavender Farm in Missouri Valley to learn more.

Haynes: Thank you, Tracy, for inviting us to the Loess Hills Lavender Farm. This is a beautiful lavender plantation, in a sense. I love that you have, what, over 500 lavender planted here. That's pretty awesome. Um, and it's been here 14 years.

It has. The previous owners had the farm 14 years. And, uh, my family decided to buy it about a year and a half ago. So lots of learning.

I bet.

Lavender is one of a homeowner's most beloved herbs because it does so much, and it's so pretty, it's got beautiful flowers, it's nice fragrance.

When you're planting it, what are some things that you need to do? Give us some tips on how to grow it.

You need to plant your lavender in a place that at least gets six hours of sun. It likes good drainage. And how you can establish that is, when you make the hole, don't use potting soil. Just use regular whatever your soil is there. And we put a good scoop of pea gravel.

It's not going to be sitting there so long that it's going to be causing any root rot. The pea gravel lets the water disperse, but it also gets the moisture that it needs.

I love the smell of lavender.

The flowers are beautiful and used in a lot of things, but it's the leaves that are fragrant as well.

The Loess Hills is a nice place to raise lavender.

Kind of a perfect soil.

[ Sniffs ]

Yeah. I know. Beautiful scents on it.

The buds, obviously, we handpick them.

So these are all hidcote?

Hidcote.

Is that the variety that you prefer to plant?

When we bought the farm, I'm fairly certain most of what we have here is English lavender. It's a more compact plant, doesn't give really long stems. But again, what we love about it is it's a repeat bloomer. So that's nice. And mosquitoes don't like lavender.

Oh, that's right.

So mosquitoes stay away.

A lot of rabbits and deer stay away too.

Yeah, lavender --

Because of that fragrance.

We love it, but they don't they don't.

They don't, yep. Well, let's go take a look at some other things you can do with lavender.

Okay. All right.

Sounds good.

Wow! Look at all the products that you can make. How many products do you have?

It's a lot.

We have bath and body products that are the most popular I guess, or people think of for lavender. But we also have lavender culinary. So I want to show you some of that.

Culinary corner.

Tell me about some of the things that you can eat with lavender.

English lavender is for cooking and baking, from coffees and teas to spices and herbs. And we also have lavender honey...

Nice.

...that you can buy.

And I see cookies.

Cookies. Yes.

Mmm!

Jellies, jams.

And then I also have a lavender fudge, lavender lemonade. And I make a wonderful lavender honey homemade ice cream also.

Oh, I completely forgot about cookies.

And now I'm focusing on lavender honey ice cream.

That sounds fantastic. I'm going to have to try some of that.

What a perfect way to end it is to have some lavender honey ice cream -- in this giant chair, which I love.

Thank you so much for having us.

You're welcome.

It has been fun.

I enjoy talking about lavender.

Excellent.

I will be back again.

Good.

Hopefully, seeing herbs and other edible plants grown in a wide range of conditions across the state has inspired you to grow these beautiful and useful plants in your own yard. Thank you for joining me on “Gardening with Steil."

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