Chapter 6: Perennials

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Welcome to the Deep Dive, your shortcut to being well -informed.

Today, we're really digging into the world of perennials, pulling out some key insights from Barbara Damrosch's garden primer.

Think of this as your essential guide, maybe your last minute lecture on getting perennials right, mixing the practical stuff with, you know, that bigger picture of sustainability and just the joy of growing things.

You know, it's funny how gardening trends come and go.

Remember terrariums everywhere or those like animal topiaries?

But perennials, they seem to stick around.

Why do you think that is?

What gives them that staying power?

Well, I think it's a mix of things, really.

There's definitely a practical economic side.

I mean, plants that overwinter outside save on heating costs, right?

Compared to greenhouses full of annuals.

Exactly.

And that ease of growing them has actually fostered a lot of small nurseries, people propagating their own plants.

But beyond that, I think it's their sheer beauty and the fact that it's always changing.

A perennial garden isn't static.

It's alive.

It evolves day by day, season by season.

It really draws you in.

That dynamic quality is definitely appealing.

Okay, so before we get too far ahead, let's just nail down the basics.

What exactly is a perennial?

Okay, good question.

Simply put, it's a plant that comes back year after year.

It renews itself, unlike an annual, which, you know, does its whole thing in one season and then dies.

Gotcha.

Now, technically trees and shrubs are perennials.

They're permanent.

But when gardeners talk about perennials, we usually mean the non -woody ones.

Ornamentals, often grown for their flowers.

Most are what we call herbaceous.

That means their leafy stems die back to the ground in the fall, but the roots stay alive underground.

Then, bam, new growth in the spring.

Ah, that moment when you see them poking through.

It's exciting.

Even seeing that first little bump of growth, you learn to recognize them.

And we often lump biennials in with them too, like fox gloves or Canterbury bells.

Right, those take two years.

Yep.

Foliage the first year, flowers the second, and they're done.

But they often self -seed, so they can kind of persist in the garden that way, fitting well into perennial beds.

And think of the classics, daylilies, peonies, irises, mums.

But honestly, there are hundreds of varieties.

So many possibilities for color and texture.

Okay, so let's tackle a common idea.

People sometimes think perennials are plant and forget them.

Is that accurate?

Not entirely.

I mean, yes, some are incredibly tough.

You hear stories about peonies or daylilies surviving untended for a century, it happens.

But a mixed perennial border, that's different.

It needs attention.

It's more like a partnership.

You've got to feed them, maybe stake some of the taller ones, cut back the dead stuff, and divide the clumps every few years to keep them vigorous.

So active involvement.

Definitely.

And another thing, they don't usually bloom all season long like annuals do.

Ah, that's a key difference.

Yeah.

Most have their moment, maybe a few weeks of glory.

The trick to getting that continuous color, that sort of rolling wave of blooms, is carceral planning.

You need to combine plants that flower at different times.

It's like conducting an orchestra, really.

I like that analogy.

Take skill.

It does.

But the payoff is huge.

And it sounds like this isn't just for, say, English country gardens.

It's adaptable.

Totally adaptable.

England's climate is great for those massive borders, sure.

But you can absolutely adapt the principles.

Many perennials are super cold hardy, blooming early spring or late fall.

And if you're in a hot, dry climate, you just choose plants suited for that heat tolerant, drought tolerant varieties.

Sustainability means working with your conditions.

Okay, so myths busted.

Let's talk design.

Where do you even planning one of these living tapestries?

Right, the planning.

Big question.

When do you want the garden to look its absolute best?

What's your peak season?

Hmm, okay.

Like spring focus versus summer focus.

Exactly.

Maybe you love spring irises, columbines, poppies.

You could tuck in some early bulbs like crocus, whose foliage will get hidden later.

Or maybe you want that high summer impact.

Think yarrow, bellflowers, daylilies.

Then you bridge into late summer with things like coneflowers or blazing star.

Or perhaps fall is your thing.

Asters, sedums, mums, Japanese anemones.

You can combine those late bloomers with plants that have great fall foliage color too.

You could even have different peak seasons in different parts of the yard.

Absolutely.

A spring garden near the house, a summer one by the patio.

Yeah.

Totally doable.

After you decide on timing, site selection is key.

Most perennials need sun, right?

At least six hours a day.

Afternoon sun being stronger.

Generally, yeah.

So maybe favor that in cooler spots or go for morning sun in really hot areas.

And think about your view.

You want to actually see the flowers facing you.

Good point.

What if you don't have full sun?

No problem.

Lots of great perennials thrive in partial or filtered shade.

Think woodland plants.

Sometimes the flower colors even look richer out of the intense sun.

But the non -negotiable.

Good drainage.

Ugh, wet feet are bad.

Very bad.

Most perennials will just rot if they sit in water, especially over winter.

So if your spot is soggy, you either need to improve the drainage or build raised beds.

And watch out for tree roots.

They are greedy thieves of water and nutrients.

You might even need an underground barrier sometimes.

Okay.

Practicality check.

For someone starting out, maybe short on time,

size and shape matter.

Huge difference.

If time's limited, start moderately.

Maybe a bed 10, 15, 20 feet long.

Be prepared for some serious work up front.

Preparing the soil though.

Right.

That initial investment.

Yeah.

Then it settles into maybe a few hours a week plus bigger cleanup days in spring and fall.

Cost -wise, you don't need to buy everything at once.

Nope.

Buy maybe a third of what you ultimately need.

Let them grow and divide them later.

Fill gaps with annuals for the first year or two.

Getting divisions from friends is super economical too.

Good tip.

End shape.

Border versus island bed.

Right.

A border usually backs up against something.

A fence, a wall, a hedge.

Tall plants go in the back.

An island bed stands alone in the lawn, so you typically put the tallest plants in the middle.

Match the shape to your house style, informal or formal, and where you'll be looking at it from.

And don't forget the frame.

A backdrop like a stone wall, hedge, or even just the house really sets off the plants.

Just make sure there's air circulation if it's a solid wall.

And edging.

Edging gives it that finished look and keeps the lawn out.

You can sink bricks or stones vertically, makes mowing easier, or just cut a clean V -shaped trench with a spade.

Simple, cheap, effective.

Okay.

So you've got the site, the timing, the shape.

How do you actually pick the specific plants and arrange them?

Do you draw it out?

Drawing it out, especially on paper, is really helpful, particularly if you're new to this.

Start by making a list of plants you like.

Note their color, height, bloom time, and importantly, their foliage.

Does it look good all season or get ratty after blooming?

Okay, details matter.

They really do.

Then you can make a chart, kind of mapping out who blooms when and how tall they get.

Figure 32 and 33 in the book are great examples for sun and shade.

Just remember, heights are approximate.

Your soil and sun will affect things.

So you use the chart to balance things?

Exactly.

See if you have too many tall plants or too much of one color at the same time.

Aim for harmony, but also contrast.

Mix flower shapes, spikes,

flat tops, daisies, fluky clouds.

Vary the leaf textures to fine leaves next to bold ones.

And think about the view.

Always.

Imagine looking from your main viewpoint.

Space plants so you see splashes of color throughout the season, not just one big clump here and then nothing.

Aim for balance, maybe repeating combinations for rhythm, but not rigid symmetry usually.

You mentioned tracing paper.

Yeah, that's a neat trick.

You can lay tracing paper over your base plan and draw just the plants blooming in, say, June,

then another sheet for July, and so on.

It helps visualize the progression.

And always think about hiding messy foliage.

Oriental poppies, for instance, kind of disappear after blooming.

Plant something bushy nearby that will fill in later.

Makes sense.

Paper plants sound useful, but maybe a bit rigid.

They can be a great starting point.

But you can also just arrange the potted plants directly in bed before you dig.

See how they look together in real space.

And look, even if you inherit plants or get gifts in an accumulation garden, having some kind of master scheme helps guide where things go.

But gardens evolve.

Plants sell seed, things mingle, allow for some happy accidents, some rule breaking.

It adds character, like threads weaving together.

As long as you set some limits.

Right.

And the absolute crucial thing,

choose plants suited to your region.

USDA zones are a start, but think about humidity, soil moisture, summer heat, too.

Sometimes a sheltered spot or winter mulch lets you push the zone a bit.

And don't be afraid to mix it up.

Use wildflowers, bulbs, ornamental grasses, even small shrubs for year round structure.

Ultimately fill it with plants you love.

Maybe it's the fragrance.

Maybe they attract bees.

Maybe they just look majestic.

It's about that connection.

OK, that connection often starts with the soil, doesn't it?

Preparing the bed seems fundamental for these long term plants.

Oh, absolutely fundamental.

You really only get one good shot at preparing the soil deep down for perennials.

The ideal time is fall for spring planting.

Why fall?

It lets the soil settle over winter.

Amendments melt together.

Spring soil can be wet and clumpy.

Since these plants are staying put for years, that initial deep prep is critical.

So mark out your bed shape first, then the hard work.

Remove all the grass and weeds, roots and soil.

Sod can be stubborn.

You might need to skim it off and compost it.

Or even cover the area with black plastic for a season.

Get rid of big rocks.

The goal is that perfect tilth.

Exactly.

Loose, crumbly, weed -free soil down to a good depth.

Enriched with lots of organic matter.

You want something that drains well but holds moisture.

Double digging, going down almost two feet, is the goal standard if you have compacted soil or hard pan.

But even loosening the top 10 -12 inches well makes a huge difference.

What kind of amendments?

Compost and well -rotted manure are fantastic.

Peat moss helps too, especially for structure.

Maybe add rock phosphate for phosphorus.

Green sand for potassium.

Lime if your soil is acidic.

A soil test really helps guide this.

You're aiming for that rich, dark chocolate cake mix texture.

Chocolate cake soil.

I like it.

Do you need fertilizer at planting?

If you've prepped the bed really well with plenty of organic matter, usually not right at planting time.

Later on, maybe top dress with compost in the fall.

A little liquid feed like fish emulsion in spring can boost heavy feeders or plants that look weak.

But go easy on high nitrogen stuff.

You'll get lots of floppy green growth and fewer flowers.

Beds prepped.

How do we get the actual plants?

Buying them, growing from seed, dividing.

All of the above.

Many common perennials are hybrids, meaning seeds won't grow true to the parent plant.

So most people buy plants or get divisions from friends.

Divisions seem like the most economical way.

Totally.

And growing from seed can be fun.

Some are easy, like blanket flower or even delphiniums, and might flower the first year.

And definitely embrace the self -sowers.

Fox gloves, columbines, lupines.

Let them pop up.

You can always move them or thin them out if they're in the wrong spot.

It gives the garden a lovely, natural, slightly unpredictable feel.

A bit of flux is good.

When's the best time to actually plant?

Generally, early spring is ideal in colder climates, just as the plants are waking up.

That's when mail -order plants often arrive, usually dormant.

You need to pot those up first.

Yeah, pot them up, let them sprout a bit, harden them off gradually before planting out.

Container -grown plants from a nursery can go in almost any time the ground isn't frozen.

But if it's hot,

loosen any bound roots and maybe cut back the top growth a bit to reduce stress.

Water everything in well.

Fall planting is fine, too, especially in milder areas.

But maybe add winter mulch and cold zones.

And spacing.

How far apart?

Good question.

General rule of thumb.

Tall plants, maybe 18 to 24 inches apart.

Medium ones, 12 to 18.

Shorter ones, about a foot.

Give them room to grow.

Overcrowding causes problems later.

You mentioned division.

How do you know when a plant needs it?

Usually after a few years,

you might see the clump getting huge and crowding neighbors, or the flowering starts to decrease, or sometimes the center of the clump just dies out, leaving a ring.

So you dig up.

The clump spring is often best in cold climates, fall in warmer ones, and carefully pull or cut it into smaller pieces, each with roots and shoots.

Then replant the divisions, adding some compost to the new holes.

It's the easiest way to get more plants.

Stem cuttings work for some types, too.

All right, so the garden is planted, growing well.

Now comes the ongoing care, right?

Keeping it looking good.

Yep, the maintenance.

Weeding is usually the biggest chore, especially in spring, before plants fill in.

A light mulch helps a lot.

What kind of mulch?

Something organic and light, like shredded bark, buckwheat holes, leaf mold, pine needles.

About two inches deep.

It suppresses annual weeds and keeps the soil moist.

Just keep it pulled back slightly from the base of the plants, the crowns, to prevent rot.

And it breaks down over time, adding organic matter.

So you top it up each year.

What about winter protection?

That's mainly for plants that are borderline hardy in your zone, or for newly planted things, especially fall planted ones, to stop frost heave.

Frost heave.

Yeah, where the freezing and thawing cycles push the plant roots right out of the ground.

You apply protection after the ground freezes.

Evergreen boughs are great.

They trap snow, which is the best insulator.

Straw works, too.

Just be aware, mulch can sometimes attract voles, little rodents that chew on roots.

Pests.

And then there's staking.

Sounds like everyone's favorite job.

Definitely not my favorite.

It's tricky to do it well strong enough, timed right, and looking natural.

The key is to stake before the plant flops over.

Before it needs it.

Exactly.

Once it's slopped, it's hard to make it look good.

There are lots of options.

Single stakes, hoops, linking stakes.

Spraying metal supports black, helps them disappear better than green, usually.

Twiggy branches, what's called brush staking, stuck in early can work well as the plant grows up through them.

Any tricks to minimize staking?

Yeah, choose naturally sturdy, compact plants.

Provide good growing conditions, enough sun, not too much nitrogen.

Sometimes you can cut back plants like asters or mums early in the season, maybe June, to make some branch out and be shorter and bushier.

Or just let plants lean gracefully on sturdier neighbors.

Okay, what about watering?

Are perennials thirsty?

Once established, they're generally more drought tolerant than annuals, especially if you've encouraged deep roots with good soil prep.

Their own foliage helps shade the soil, too.

But you'll need to water new transplants, and maybe during long dry spells.

When you do water, water deeply.

Soak the ground thoroughly, maybe once a week in dry weather, rather than light daily sprinkles.

You want the moisture to go way down.

And water the soil, not the leaves, if possible, to reduce fungal diseases like mildew.

Choosing drought tolerant plants is obviously a smart move in dry climates.

And pests and diseases, generally.

Not a huge issue.

Usually not a crisis.

You might get some aphids or leaf miners.

But often, beneficial insects will keep them in check without spraying.

For fungal things like powdery mildew, good air circulation is key.

Don't overcrowd plants.

Clean up diseased leaves.

Keep plants healthy with good soil and consistent moisture.

And look for disease -resistant varieties when you're choosing plants.

You mentioned cutting back.

Pinching, too.

Right.

Pinching is removing just the growing tips, usually with your fingers.

It encourages branching, making the plant bushier, more compact, often with more flowers.

Mums are the classic example.

Cutting back is more drastic.

Maybe taking off the top third of a plant mid -season to control height or promote later bushier growth.

And then there's deadheading.

Removing the spent flowers.

Essential.

Not strictly essential for the plant's health.

But it definitely makes the garden look tidier and often encourages more blooms.

The plant puts energy into making more flowers instead of seeds.

It also stops unwanted self -seeding if the plant isn't a hybrid you want to save seed from.

You have to deadhead everything.

It depends on the plant and how much time you have.

Some benefit more than others.

Sometimes you just snip the flower head.

Other times you cut the whole stock back.

In a big garden, you might just tackle the most obvious offenders like gooey old daily liblooms.

But sometimes you want to leave the seed heads for winter interest, like on comb flowers or sedums or for birds to eat.

Right, food for wildlife.

What about fall cleanup?

Cut everything back or leave it standing?

Personal preference, really.

Leaving stems up provides winter interest, traps snow, and gives shelter for beneficial insects and birds.

But some people prefer a tidier look going into winter.

A compromise is often good.

Cut back things that get really floppy and messy and might harbor voles, like maybe Siberian iris foliage.

Leave the sturdy upright things like grasses or sedum for spring cleanup.

If you clean up in spring, just do it before the new growth gets too tall, maybe an inch or two.

It really does sound like a garden is constantly changing, a living thing.

What if things aren't working or an older garden just looks tired?

That happens.

You live with it, you learn, you start recognizing plants just by their leaves, their habits.

When a garden feels depleted or chaotic, maybe it's time for a renovation.

Like a complete overhaul.

It can be.

In early spring, you can actually dig everything up, temporarily plant them in a area called healing in, just covering the roots to keep them alive.

Then you rework the whole bed, add compost, improve the soil like you were starting fresh.

It's the perfect time to divide those overcrowded clumps and get rid of any really persistent weeds that snuck in.

The chance to edit too.

Exactly.

Be honest.

Did that phlox color ever really work?

Was that plant always floppy or disease prone?

Now's the time to compost it or give it away.

Don't feel obligated to keep plants that aren't performing well or pleasing you.

And smaller changes, moving just one plant.

You can do that too.

If something's clearly in the wrong spot, try to move it with a good chunk of soil around the roots, water it in well.

Spring or fall is usually best.

Avoid the hottest part of summer if you can.

If the timing's bad, just make a note for later.

Give a garden journal or reminder list.

Photos are great too.

They really help you remember how things looked.

Speaking of plants getting out of hand, let's talk about spreaders.

Some perennials are a bit too enthusiastic, right?

Oh yes, the vigorous ones.

Or maybe even invasive.

It's a fine line sometimes.

Some plants are just vigorous growers they spread by roots or seed readily, like bee balm.

Great for pollinators, but needs regular weeding out or containing.

Others can be genuinely problematic, almost thugs.

Like goutweed.

Goutweed is notorious.

Pretty variegated leaves, but it can take over everything.

Some things, like certain ornamental grasses or loose strife, can even escape the garden and damage local wild ecosystems.

Some are actually illegal to sell in certain places because of that risk.

So important to know what you're planting.

Crucial.

Check with local experts or horticultural societies if you're unsure about a plant known to spread.

Understand its habits.

Can you manage it?

Does it pose a threat?

Sometimes vigorous plants are fine if you give them space or boundaries, but true invasives should be avoided.

The book lists quite a few examples explaining their habits.

It's all about informed choices.

That perennial palette section sounds incredibly useful for making those choices.

It really is.

It details 50 common reliable perennials, everything from Japanese anemones to yarrow, covering their needs, their habits, specific varieties.

It gives you a solid foundation for planting.

So bringing this all together, what's the big takeaway for someone listening, maybe thinking about starting a perennial garden we've covered a lot?

From the basic idea through planting, soil prep, planting, and all that ongoing care,

it seems the core message is, well, it's not thoughtful planning up front, right?

Absolutely.

That planning, combined with really good soil preparation, sets you up for success.

And then it's about consistent but adaptive care, watching your plants, learning their needs.

It's more than just pretty flowers, though.

It connects back to bigger ideas.

I think so.

It's about creating a sustainable space, working with nature, not against it.

It fosters that connection, that understanding of cycles.

And honestly, it's incredibly fulfilling to nurture something beautiful and lasting.

Maybe think about this.

What can that cycle of perennials dying back each winter, then bursting forth again in spring, teach us?

There's a resilience there, isn't there?

But a constant renewal.

That's a lovely thought, resilience and renewal.

Maybe the next step for you listening is just to notice a perennial in your neighborhood, or start imagining what you could create, even in a small pot or corner.

See where that takes you.

Thank you for joining us on this deep dive into the world of perennials.

We hope this guide, this sort of last -minute lecture, has given you some solid insights and maybe sparked some gardening ideas.

Until next time, from the deep dive team,

keep exploring, keep growing, and keep digging into what makes your world bloom.