DougGreensGarden

Four Things That Kill Overwintering Perennials

Here are the four things that kill overwintering perennials.

The first is too-wet soil. A soil that holds moisture over the winter tends to rot plant crowns. A winter that has an excess of freeze-thawing will create wet soil with a layer of ice over top and this is certain death for many plants.

While I used to keep my mulch over top of all my plants in the winter, I now tend to pull it back from all the crowns at least 8-inches. This space allows the crowns to breathe and lose excessive moisture (as long as there isn’t a layer of ice on the soil). The plants also come up faster in the spring with this clear area around the crowns.

If you have problems with overwintering perennials or if you want to push the gardening zone on perennials, the single most important thing you can do is increase the drainage in the garden or grow those tender perennials in well-drained areas.

Excessive cold will kill tender perennials planted in colder areas. Butterfly bush is an excellent example. It is sold in many garden centers as a hardy perennial but in USDA zone 4, it is marginally hardy.
Buy plants that are hardy in your zone

Old age. Many beginning gardeners don’t understand that the lifespan of a perennial isn’t “forever”. Most perennials live 3-5 years before they go to the great compost heap in the sky. The longer-lived ones (peonies, daylilies, hosta, astilbe) can easily reach 15-20 years but most others are shorter-lived.

Just Because: In my perennial garden, I plan on losing 15% every year just “because” – with no reason other than “it’s dead”.

Combinations. In the nursery trade, we know that winter will kill a different plant every year. Some year, the unique pattern of weather might wipe out Shasta daisies. The next it might be bleeding heart. This won’t happen in every garden but there will be a general regional plant loss that will mystify every garden expert and cause a run on that plant in the garden shops. Plants that are otherwise bone-hardy will suddenly die with no apparent reason. But it sure annoys the heck out of gardeners.

Mulch Is An Excellent Way To Increase Success With Overwintering Perennials

Mulch helps even out the swings in temperature and it also helps hold the snow over top of the plants. You’ll lose more plants in a year with a fluctuating spring (from high to low and up again) when the plants are thawed out than you will in a year where everything stays frozen until it is time to grow. While keeping my plants frozen a little longer with a thick mulch may mean the early spring bloomers are a few days late blooming, I do know they are alive.

One of the greatest “mulches” for tender perennials is to put old Christmas tree branches over top of the very tender plants. This holds the snow in around the plant and keeps them happy until spring. Remove the branches when the snow melts.

How To Think About Your Overwintering Perennials In The Spring

Do not give up on a plant until you know the plant. For example, every year I’ll get letters asking why this plant or that plant is dead. And I write back suggesting they wait another few weeks because the plant is either a notoriously late starter (Coreopsis verticillata) or just sulking a little (hibiscus).

I moved my hibiscus to a holding garden in October 05 and then to its garden location in April 06. It finally showed up in early July with two shoots, grew six-feet tall in 6 weeks and started blooming the end of August. Go figure. Even I had given up on this one but it surprised me.

If you’re poking around, you can check to see if the root is soft and mushy (dead) under the mulch or whether the root and eyes (small growing points) are hard (alive). If a lavender or woody plant, you can gently scrape the bark with your thumbnail and if it is bright green under the bark, it is alive. If brown, that branch is dead. Enough dead branches and the plant is dead.

This always assumes that a plant is installed in the right light and soil areas. If you try to grow a plant out of its preferred location, you stress it. If you stress it enough, it will winterkill.

Clay soils that hold moisture will rot out roots of plants that want drainage. Plants that want full sunlight and are planted in part sun will go into the winter weakened.

I note you may get away with this for a few years but eventually, the stress of the growing condition will show itself over the winter.

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Four Simple Steps To Growing a Great Organic Lawn

The first steps in growing an organic lawn means understanding four simple techniques. Luckily, these are easily described and easily accomplished.

Step one: make the lawn thick.

Every fall, you’re going to add two to 6 pounds of grass seed per thousand square feet of lawn.

If your lawn is lush and green now, then 2 pounds is acceptable.
If the lawn is sparse and weedy, then you can add four to as high as 6 pounds per thousand square feet.

This will increase the number of grass plants per square foot in your lawn. And because grass is an effective competitor, it will choke out the many weeds.
We call this overseeding and we’d do this. When the night temperatures cool down in September.

Step two makes the soil fertile

Fertile soil feeds your grass plants and make them healthy. The simplest way to do this is to add compost at the rate of 2 pounds per thousand square feet in the spring and 2 pounds per thousand square feet in the late fall.
Compost will activate all the microorganisms in the soil and these in turn work to increase the health of each individual grass plant.

This is a good point in this note to remind you that a lawn is composed of thousands of individual plants. I invite you to consider you’re not “growing a lawn” but instead you’re “growing thousands of plants” that make up a lawn.

Organic matter is the lifeblood of good soils. So we’re going to do two things, to ensure a high organic matter content in your lawn. The first is to add one bale of peat moss per thousand square feet in the early spring. The second is to set your lawnmower at its highest setting and allow the clippings to stay on the lawn after mowing.
For the average lawn, these simples how-to steps will improve fertility greatly.

Step three: controlling weeds organically.

There were two basic types of weeds we need to control.

The first are those annual weeds, whose seeds germinate first thing in the spring.

A good example of this is crabgrass. Crabgrass is an annual, and frankly, at the beginning stages, most gardeners can’t tell the difference between crabgrass and turf grass. Annual seeds are controlled by adding corn gluten at the rate of 20 pounds per thousand square feet of lawn.

Adding corn gluten every spring, will reduce or eliminate annual weeds within three years. Note this is why we spread our grass seed in the fall, because corn gluten will stop grass seed from germinating as well.

Perennial and established weeds will not be controlled by corn gluten. This will require a little work on the gardeners part.

I use a simple tool called a spud. It has a long handle and a forked metal blade that cuts perennial roots off. I repeat this several times in the spring and the vast majority of weeds are finished. The spud kills established weeds and the corn gluten stops them from reappearing.

Click here to check out my Organic Lawn Care ebook.

Step four: controlling insects.

A healthy organic lawn will be less bothered by insects, and any damage is quickly repaired by the lawn itself. After a few years of organic fertilization, you’re going to find that insects and pests are not a problem.

In the organic lawn, white grubs and other pests are easily controlled using predator nematodes and chinch bugs are controlled with insecticidal soap drenches.

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Seed Starting: The First Things To Know

There are several things you have to understand about seed starting.

Seeds germinate based on a change in hormones within the seed. For the most part, annual seeds germinate when the soils warm up in the spring. So home gardeners need to be able to create warm soils.

They germinate when adequate moisture is available so we have to provide appropriate moisture. Note this doesn’t mean a lot of water – it simply means what the seed requires.

I note this is generally high humidity around the seed coat, not being soaked in water.

Seed starting most annual plants is easy and this activity makes a wonderful family project that delights small children as well as their gardening parents.

I suppose non-gardening minds will ask if there is a similarity between the delights of small children and the delights of gardeners and I am pleased to be able to answer in the affirmative.

These similarities are why there are no old gardeners although you may see older people gardening

Containers.

The first step in seed starting is to choose an appropriate container and while gardening magazines promote a variety of things, I use flower pots.

They work well, hold enough moisture to prevent excessive drying out and are relatively inexpensive. Most of us have a few lying around the place so they aren’t hard to come by or expensive either.

Clean them thoroughly; there is no sense starting good seed and have them die because of bacteria from old soil on the pot.

If you can’t be bothered cleaning them out – use pots that have sat in the shed for a year and the soil is thoroughly dried out. (Note there is research now suggesting cleaning isn’t necessary *if* the pot has been left empty for a year between uses.)

Bad “guys” are pretty much toast if the soil has been dry that long. What you don’t want to do is go from fresh soil to fresh soil to fresh soil – without cleaning out the pot.

Yes, you can use just about anything that holds soil but do understand that paper products such as egg cartons (beloved of back-to-earth magazines) will dry out fast and will be harder to maintain soil moisture because of their smaller sizes.

Soils

I use an soilless mix such as Promix for my seeding because it is sterile, and weed free.

Few things are as frustrating to find the plant you have been nurturing for several months on your windowsill is in reality a large weed with no redeeming floral graces. That’s experience talking.

If you really, really, want to use potting soil, (I don’t recommend it but…) put it into the pot leaving one half to one inch of space between the soil top and the rim of the pot and then slowly pour boiling water into the pot until the water runs freely out the bottom.

Let the soil cool before seeding. I don’t usually recommend potting soil because it comes in a wide variety of qualities and can compress during the growing cycle.

Do not use garden soil as it compacts terribly and seed germination rates will be much lower than in artificial soil.

Compost/Manure in the Soil

Here’s the real deal. Never use manure in a seed starting soil. So if you have one of those “wonder” soils in packages that contain it – do not use that soil for seed starting. There are simply too many problems that come along with using manure in this way.

Here’s the deal with compost. If it is fully composted, if it has been hot composted to destroy pathogens, you can actually germinate and grow your seeds in 100% compost.

But.

If it isn’t perfect compost (and you’ll seldom buy perfect compost I note) then using it will kill off your seeds/seedlings.

If in doubt, try growing tomatoes or cress in a 100% trial pot of the stuff. If the cress grows well, it is OK to add. This is the most sensitive indicator. Tomatoes will grow in almost-OK and if they grow, then most other things will be OK to have some of this compost added to the mix. If neither of these plants does well, do not add any of that compost to the mix.

If it isn’t perfect compost (and you’ll seldom buy perfect compost I note) then using it will kill off your seeds/seedlings

There are many examples of poor compost taking out seeds, seedlings and even young plants in fields.

It is much better to avoid using compost in seed starting mixes but there are some gardeners who swear by their methods. Not me. I want consistent soil starting and growing seedlings.

Hormones and Additives

Some advanced gardeners use hormones such as Gibberellic acid-3 (GA-3) to induce germination in tough-to-start seeds.

This is pretty specialized gardening and frankly, is a waste of time for all but the very toughest of seeds. I’m not going to tell you how to do this in this introductory article because you can do more damage to regular seeds by using this stuff. I will write about it in another section.

It’s like putting jet fuel in an old volkswagen – you’ll simply kill the engine/seed rather than get extra speed.

Let me simply say that I never used GA-3 in my nursery and we grew over 1800 varieties of perennials and 6-800 varieties of annuals every year.

There are some seeds, e.g. species Rhododendrons, that can be a bit tricky to grow and the nursery solution is to scarify (mark) the seed coat so that moisture can get through the shell of the seed to induce germination.

Different kinds of acid are used in commercial seed starting of some rare plants (Liquid Plumber was a favorite) to get higher germination rates but given that you’ll be happy with a plant or two rather than 100% germination, you don’t need to use phosphoric or sulphuric acid.

One thing that has been shown to improve germination rates on home scale sowing is the use of seaweed teas. The hormones in seaweed act to stimulate seeds – natural GA-3 – and you’ll get a slightly better germination percentage if you water once or twice with this product (do it right after you sow and then forget about doing it again).

Water

Don’t use soft water if at all possible. There’s a potential for salt buildup and seedlings don’t like salt.

Always use warm water when watering any kind of seedling flat – from annuals to perennials. The only exception to this is outside watering. While it might be a great idea, it’s a ton more compulsive than I’m ever going to be and no nursery person I know does it.

If a seed is tough enough to germinate outside, it gets what it gets.

I think you’ll find my ebook on propagation will answer a great many of your questions.

Why Do My Daffodil Buds Die?

Why do my daffodils buds die? They come up normally with a wonderful bud and then fail to open and die?

Doug says:
If it’s an older variety, the do tend to get bud blast (for which there is no cure) and have to be dug out and thrown away.

Some of the modern varieties will do this if the bulbs are overcrowded.

Dig them up this fall, divide and replant immediately if they are overcrowded.

There is also a disease called “Fire”

This causes the flowers and foliage to rot away but doesn’t bother the bulbs. Cleanliness is next to godliness on this one along with some serious spraying with lime/sulphur to control the fungus.

Click here to check out my ebook on growing all kinds of bulbs

Bulb Mites

Bulb mites will also do this causing the buds/flowers to deform or not open.
The cure here is to dig the bulbs and soak them in an insecticide (soapy water) for 24 hours that kills off spider mites. Dig in the fall or after the leaves have yellowed.

That’s roughly your choices. I also note that environmental stress is the primary cause of flowering problems but it may not be here.

How to tell which is the problem?

Personally, I’d be looking for the overcrowding first if the daffodil bulbs are over 5 years old.

Spraying the daffodil buds with lime-sulphur is a good idea in any case to knock back any fungal problems and you can do this immediately.

Then I’d check for bulb mites (maybe dig one bulb up and examine with magnifying glass in all the little cracks and under the bulb scales). Spraying with lime-sulphur is a good idea in any case to knock back any fungal problems and you can do this immediately.

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Water May Not Spread Equally In A Container Garden

This research article focused mostly on hydroponic water using “watering from below”. If you water your houseplants or containers by setting the pot in a saucer and then filling the saucer, it’s the same thing.

Turns out the water only goes up about 80% of the way in the container and the top 20% will remain too dry.

I have done this with my seed starting trays. I water them from the bottom so I don’t disturb the soil or the tender seedlings. But I have noticed I do have to heavily mist the tops to keep them moist.

Now I know why and I’ll go back to watering up top.

(In the nursery, I had misting systems that kept the tops constantly damp so there wasn’t an issue but on the home scale, I learned something this week) 🙂

Bottom line: water from the top of the container.

The original research report is no longer available. Feb/19

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