Garden Menagerie

This Duddington Place second-story catio has all the bells and whistles, and blends in perfectly with the architecture.

As every residential garden designer knows, a homeowner’s pets are your clients too. Pets’ well-being, habits, quirks, and age need to be taken into account to arrive at an attractive and sustainable garden solution that works for humans, pets, and plants. Dogs and cats are the most common household pets, so today let’s focus on them.

While these two types of four-legged friends may seem very different, they have many garden requirements in common. They need to be kept enclosed, safe, hydrated, thermally comfortable, amused, and happy. As with humans, gardens that offer comfy places for napping are especially popular with dogs and cats. Providing places to observe the action undetected are valued by cats (who enjoy perches) and dogs (who prefer being under things like a table or deck).

We will hear from a garden-cat expert, Cynthia Chomos, and her garden-dog counterpart, Cheryl Smith. Chomos is founder and designer of Catio Spaces (, and Smith is author of “Dog Friendly Gardens, Garden Friendly Dogs” (2004,

Common Garden Plants Toxic to Pets
First, a topic of concern for both cats and dogs is poisonous garden plants. This list is not comprehensive and does not include plants that may harm pets in other ways, such as thorns at eye level, which should also be avoided. The following information is from Pet Poison Helpline ( Pets with known exposure to these plants should be examined and evaluated by a veterinarian and treated symptomatically.

  1. Autumn crocus (Colchicum autumnale). The autumn crocus, different from the common spring crocus, is highly toxic and can cause severe vomiting, gastrointestinal bleeding, liver and kidney damage, and respiratory failure. Signs may be seen immediately but can be delayed for days.
  2. In the same family as rhododendrons, azaleas can have serious effects on pets. Eating even a few leaves can result in vomiting, diarrhea, and excessive drooling; without immediate veterinary attention, the pet could fall into a coma and possibly die.
  3. Lilies (toxic to cats especially). The more dangerous, potentially fatal lilies are true lilies, and these include tiger, day, Asiatic, Easter and Japanese show lilies – all of which are highly toxic to cats! Even small ingestions (2-3 petals or leaves) can result in severe kidney failure. If your cat is seen consuming any part of a lily, bring it (and the plant) immediately to a veterinarian for medical care.
  4. These flowers contain lycorine, an alkaloid with strong emetic properties (it triggers vomiting). Ingestion of the bulb, plant, or flower can cause severe vomiting, diarrhea, abdominal pain, and even possible cardiac arrhythmias or respiratory depression.
  5. Lily of the valley (Convallaria majalis). This plant contains cardiac glycosides which cause symptoms similar to digitalis (foxglove) ingestion. Symptoms include vomiting, diarrhea, a drop in heart rate, severe cardiac arrhythmias, and possibly seizures.
  6. Tulips and hyacinths. Tulips contain allergenic lactones while hyacinths contain similar alkaloids. The toxic principle of these plants is concentrated in the bulbs, rather than the leaf or flower, so make sure your dog isn’t digging up the bulbs in the garden. Chewing or ingestion of plant parts or bulbs can result in irritation to the mouth and esophagus. There’s no specific antidote, but with supportive care from the veterinarian (including rinsing the mouth, anti-vomiting medication, and possibly subcutaneous fluids), animals do quite well. With large ingestions of the bulb, more severe symptoms such as an increase in heart rate and changes in respiration can be seen, and should be treated by a veterinarian. These more severe signs are seen in overzealous chowhound Labradors.

Keep other toxins safely away from pets (and human children), including herbicides, fertilizers, and pesticides. Even better, practice organic gardening and eschew these products altogether. Consider the effect mosquito spraying may have on pets, since it is toxic to bugs and therefore the birds that eat them.

What Do Cats Want?
Unlike dogs, we designate our cats as “indoor,” “outdoor,” or both. Entrepreneur, designer, and cat lover Cynthia Chomos says, “Indoor-only cats like fresh air and the stimulation of nature, just like their outdoor counterparts, but if left to roam outside they’re in harm’s way.” Outdoor cats are responsible for songbird predation and may themselves be preyed upon in urban environments by critters like possums or even hawks.

In 2014, Chomos created Catio Spaces in Seattle, Wash., providing affordable, stylish, and downloadable catio plans as well as design/build catios. Her DIY catio plans are intended for carpenters of all levels including novices, and range from $39.95 to $69.95. A portion of all proceeds is donated to various animal welfare organizations.

On the Hill, doting cat owners Bert Kubli and Mark McElreath have created a second-story catio on the back of their home at Duddington and Second Street SE. Besides a ground-floor garden filled with animal statuary rearranged for every holiday, the screened catio, for Maine coons Lera and Luba-Lusya, contains cat amenities such as a stairway to heaven and a set of carpeted platforms at tree canopy level, where the girls can catch a breeze and birdwatch at a safe distance.

Eastern Market cat-neighbor Omar is an indoor/outdoor cat whose owners had a garden installed in their new home, which I had the pleasure of designing. Owner Marc wanted Omar to be able to enjoy the new space but not jump from the edge of the oversized tree planters to the adjacent alley below, so he designed and personally installed a top-rail fence feature that has done the trick so far. It consists of two parts: first, plain black gutter guard mesh bent at a 90-degree angle and tacked to the top of the fence; next, pieces of plastic bird spikes by Bird-B-Gone tacked within the gutter guard. This created the appearance of a complex barrier which Omar, so far, has not ventured onto, allowing him to enjoy the garden, which he regularly does.

Consider a catnip area or planter for your garden or catio where your cat may nip and nap at will.

What Do Dogs Want?
According to new garden and adoptive Labrador owner Victoria, Norman and Wally like to hang out in the shade under the outdoor dining table. For potty-purposes, we have designated an area of about 25 square feet in a back corner of the garden for liriope, where Victoria plans to train them to do their business. Since they are fully grown, this will take persistence, which Cheryl Smith’s book on dog-friendly gardens claims is possible. Hopefully, these gregarious brothers will leave the new plantings alone and keep enjoying their shady patio, while peeing in the liriope, which should be tough enough to withstand the abuse. If not, it’s easy enough to replace it.

Dogs will want to dig or not dig, based on breed and age. Terriers and dachshunds are born to dig (terrier comes from the French “terre,” earth). Other breeds like to create shallow depressions in the ground in which to nap. With such breeds, why not create a digging pit in a shady area, using illustrations from Smith’s excellent book? Just be sure to keep it away from tree roots to protect your tree. If possible, consider using raised beds and/or large planters to discourage digging. Space permitting, give your dog a circuit to run around, to keep things interesting. Always provide access to fresh water. A small kiddie pool would be a great summer garden addition for your dog and might help keep it happy enough to abstain from digging up the plants.

Wishing you and your pets a happy and safe summer!

Cheryl Corson is a landscape architect, writer, and animal lover in private practice designing on the Hill and beyond. She is author of the “Sustainable Landscape Maintenance Manual for the Chesapeake Bay Watershed” (