It's Only Natural: Common Late Summer Issues

Many things can happen in the garden that may make you panic and think all is lost. For this, we are starting a new blog series “It’s Only Natural”. We will address some things that may come up, what they mean and some ways to help. For this edition, we will focus on common late summer issues.

Late in the summer the garden almost always looks somewhat sad. The days have been long and hot and there has been little rain. The plants are stressed. Many have gone dormant during the hot weather as a method of survival. This means little new growth is occurring.

Watering is the most important thing in the late summer. It is good to give your plants deep water. This helps develop a strong root system. Shallow watering often doesn’t reach where it needs to and dries up quickly on the surface due to the extreme sun in late summer.

Common issues

Things are looking distressed. Plants have some yellow leaves.

This is mostly happening because of lack of water and the heat. The plants are shedding excess leaves to conserve what water they have for the rest.

Tip: Remove dead or yellow leaves from plants. Not only does removing the dead parts allow for airflow, it also allows the plant to conserve it’s energy for growth.

Powdery mildew on perennials

Mid to late summer disease starts becoming visible on plants. Powdery mildew is chalky white fungal disease that coats leaf surfaces. This won’t kill the plant but it will weaken it overtime. Annuals are very susceptible to it but it is also common with some perennials such as verbena, monarda, and tall garden phlox.

Tip: Use Safer and Bonide brand products to combat this. These are safe organic options.

Blooms are spent

Some perennials have finished flowering by late summer. Now is a good time to notice empty spots in the garden. Your early bloomers have finished flowering and now you can notice a few areas where you may like to add in some late blooming plants.

Tip: You can deadhead all those spent flowers (or if you’d like to save the seeds leave them on until dried out). Deadheading is a good way to tidy up the garden and also encourages new growth. Some spent blooms look nice to leave into fall and winter, and some may be left to attract birds- it depends what you’d like for your garden.

Late season weeds may have taken hold of your garden

In August, it seems like we all were gone on vacation. Gardens don’t take vacations though and while you were away, the weeds took over.

Tip: Some effort is needed to solve this issue but once you get rid of those guys then your garden will look a lot neater and it gives your perennials more room for growth.

Edibles

Things are huge and out of control and are probably a bit heat stressed as well. Like with the rest of your garden, it’s a good idea to go through and clean out any yellowing or dead parts. This will help prevent mildew and disease spread.

APHIDS!

Aphids may have taken over some plants by now. If you planted nasturtiums in your edible garden at the beginning of the season, this was a great idea! Nasturtiums attract aphids away from your other edibles.

Tip: They may be super infested by now and you might just want to remove them. Sunflowers are also good to plant near edibles, as they will also attract aphids away from your other plants.

Cracking tomatoes

Some of your tomatoes may have split. This is caused by extreme temperatures and periods of dry weather, followed by heavy rain.

Tip: Grow resistant varieties. When cracks do appear, harvest the tomato immediately and it can be eaten with no problem. Try to keep the soil uniformly moist.

You may think your edible garden is done for the season but you can actually start some cool weather crops now. Spinach, lettuces and radishes are good to start now. Check out this site to see what you can plant.

Rooftop Gardening Guide

Rooftop gardening and gardening in the ground are VERY different things. There are many factors that you need to consider when rooftop gardening. We have created a guide to some of these factors.

This is based off experience and is our rule of thumb. It’s not proven science...yet.

Rooftop garden with Red Cedar and Baptisia by Staghorn NYC (us!)

PLANTS

When choosing plants, you want to make sure they are super tough and hardy. For help making this selection, check out two of our other posts to read about some super tough perennials and things to consider when selecting rooftop trees.

GROWTH

This applies to growing in planters on ground level or roof level.

Plants grown in the ground grow faster and larger than when grown in planters.

When a plant is grown in ground, it’s roots have ample room to reach and grow. In a planter, roots are limited to the space of the planter. The above-ground plant generally grows as much as its roots can support. When root growth is limited, the above-ground plant’s growth is also limited.

Also, some faster growing plants can become root bound in a planter after time and will need to be repotted. Larger planters allow for more root growth and thus larger plants.

Root bound plant

WINTER

Plants have hardiness zones which are the areas in which they are capable of growing well. This is dependent on the minimum temperatures which the plant can stand. Zone 1 is pretty frigid and zone 12 is the tropics. New York is said to be zone 7.

Link to map

As soon as you put a plant into a planter, you should consider that environment 1 zone lower. This is on ground level, not on a terrace/rooftop/or balcony - so now we're talking zone 6.

Put that planter on a rooftop and drop it down another zone - zone 5

If you're over 10 stories high, a good rule of thumb is to take it down another zone - zone 4

A good comparison is the bridge freezes before road in the winter  - just like a bridge, a planter will lose heat from the top and from the sides, and to an extent from the bottom, causing it to freeze faster. An in-ground garden, like a road, only loses heat from its surface, and otherwise remain insulated by earth

WIND

Amsonia blowing in the wind

Some rooftop/terrace/balcony gardens are taken to the next level of extreme with the wind factor. Depending on how protected or exposed your space is will determine how important the wind factor is in your plant choice.

Evergreens are the only plants that keep their leaves through the frigid, windy winter months. Thus, they are the only ones that experience the worst the wind factor has to give: winter burn. Here is an article about preventing and dealing with winter burn.

The size and shape of your plants will also determine how well they will hold up in the wind. Top heavy plants, ones with large blooms are more susceptible to breaky in the wind. For example, peonies won't do so well, but amsonia is great.

WATER

Since planters are confined spaces, they can dry out pretty quickly, especially on a dry, windy, sunny day on a rooftop. They should be watered between 4-5 times a week depending on the size/depth of the planter.

We highly recommend irrigation systems to all of our clients, friends, families, and complete strangers. They save lives, plant lives.

PLANTERS

Planter garden by Staghorn NYC

Terracotta - Don't bother unless your plants are small and you're cool with them being possibly disposable.

Wood - Be careful here. Quality wood and craftsmanship can give you a great planter that'll look beautiful and last years. We recommend going with custom built. If you can’t, make sure it’s good quality teak, cedar, or ipe, otherwise you’re looking at a rotten mess a few years down the line.

Fiberstone - A good buy, pricey, but worth it. Comes in nice colors, very lightweight and easy to move, super sturdy, and won't crack in winter.

Metal - Wouldn’t mess with anything outside of Cor-Ten steel

Plastic - May surprise you with some positives, but it’s plastic, so manage those expectations.

Top 5 Super Tough Perennials

Want to get into gardening but the few plants you've ever had have all died? 

We get it, you're busy or forgetful or you like to travel and you just aren't around. 

Whatever reason you have, you just can't manage to keep your plants from croaking. 

Well you are in luck! There are super tough plants out there that you could put in the ground and almost forget about completely.

Here is a list of our top five hardy perennials:

Baptisia, False Indigo

Baptisia is a beautiful, tall plant with lupine-like flowers. It's drought resistant and does well in the sun or part shade. It blooms in late spring and summer. In the fall the foliage turns silvery-gray. It's also loved by the birds and the bees.

Nepeta, Catmint

Nepeta is a very easy growing plant. It has a sprawling growth habit, so if all your other plants died, don't worry this guy will fill in. It has aromatic foliage and little lavender flowers. The bees love it.

Echinacea, Coneflower

Coneflowers are super easy and come in any color you could want. They do well in sun or some shade and can grow 2-5ft high. Bonus: they attract birds, bees and butterflies to your garden.

Rudbeckia, Black-eyed Susans

Black-eyed Susans bloom profusely even in the most challenging garden conditions. They prefer full sun and are drought resistant. There are many species of Rudbeckia native to North America. Some may act as annuals while others, perennials. Check the hardiness of each species for your zone. And like most native plants, they will attract birds and butterflies to your garden.

Amsonia, Blue Star

Amsonia is an easy growing, drought tolerant plant. It has beautiful clusters of blue flowers in late spring. It loves full sun and can tolerate a variety of garden soils. In the fall, the foliage turns brilliant shades of gold. Butterflies love it.

Before & After: Prospect Heights Backyard Garden

The Prospect Heights, Brooklyn backyard featured in this post is a big space (by Brooklyn standards) that needed some big changes.

Our challenges: removing invasive Japanese knotweed, building a bluestone patio, creating a sense of borders without constructing a fence, and designing a kid/adult/pet friendly space that the whole family could enjoy.

Our solutions: curvaceous planting beds to soften the "rectangle" and balance out the lawn, tons of non-toxic native perennials, grasses, shrubs, and trees for 4 seasons of interest, a raised vegetable bed, and a natural play area with re-purposed local tree stumps.

Check out this project and more on our website.

Garden Design Challenge: Bee Allergies

Recently, I encountered a project challenge that was entirely new to me – How do I design a garden for a client with a severe allergy to bee stings? First of all, the client understands that a 100% bee-free garden isn't possible unless we're talking about constructing some sort of bio-dome, and we're not. After doing some research I found that what we can do is design a garden space that is, shall we say, less alluring to bees. Normally, I design gardens that do quite the opposite by re-establishing and/or supporting native habitats – and pollinators (like bees) are a crucial part of that. But with some careful finagling I think it'll be possible to design a healthy, sustainable garden without attracting too many stingers.

How do we begin? We think like a bee.

So what makes a flower attractive to a bee? A few key characteristics:

• structure–easy access to nectar/pollen. Can the bee's body/proboscis reach the nectar? If the blossom is too long and narrow, no.

• scent–pretty straight forward. Most highly fragrant flowers have a lot of nectar - a big draw for bees - so it's something to consider when selecting plants for bee avoidance.

• color–blues and purples are easiest for bees to see, and therefore, especially attractive. Reds, on the other hand, looks black to a bee, so they generally ignore them. 

Now that we've got this information, some strategic choices can be made in selecting plants for the garden that won't attract bees, but will attract other important wildlife like hummingbirds and butterflies. 

Here's a list to get you started:

Cardinal flower – A great native flower that the butterflies and hummingbirds adore.

Red Coneflower – Double petal or classic, it's a gorgeous pop of color. 

Crocosmia –Not a native, but the hummingbirds still love it. 

Double-petal or "ball" Dahlias – The petals are too compact for most bees to get to their nectar, or they're sterilized. They come in a delightful array of colors. 

Penstemon– Another native, some bees won't be able to reach the nectar because of the shape of the flower.

Coreopsis "Mahogany Midget" – More reds, prolific bloomers. 

Gaillardia "Sundance Red" or "Arizona Red"– Native and also red, the butterflies are big fans. 

Feverfew– A nice non-red option, and bees are generally turned off by it's fragrance.

Columbine– Native or not, some bees struggle to reach the nectar because the flowers are facing downwards.

Ornamental grasses– Go to town with these guys. They're an important part of a healthy ecosystem, but the bees aren't interested

Ferns– Lush and lovely, they're great for you and of little interest to the bees. 

Want more info on all things bees? Check out the American Beekeeping Federation's website