What the heck is wrong with my vegetable garden?
“Four essential physical factors affect how successful your garden will be: temperature, soil, light and water. … Considering these factors from the beginning will take you a long way toward the delicious harvest of your dreams.”
— David Deardorff and Kathryn Wadsworth, “What’s Wrong with My Vegetable Garden?” (2011)
This week I’ve been half-heartedly removing rosemary bushes from the Bard’s Garden at Hanley Farm. I wanted to create an aromatic rosemary hedge in the Winter’s Tale garden plot, but several of the dozen young shrubs I planted four years ago have not been growing happily ever after.
Each spring, entire branches of the now 3-feet-tall rosemary bushes have died back. In addition, the branches have tended to spread out from the lower trunk like a cup with a large gap in the middle of the bush, and this growth habit has not made an attractive border after all. Drats!
Rosemary is a Mediterranean herb that likes warm, sunny weather, mild winters and well-draining soil. It doesn’t require a lot of moisture or nutrients in the soil to grow well. It’s not a particularly fussy plant to grow, so what’s wrong with the rosemary bushes in my garden?
According to Deardorff and Wadsworth, I can narrow down the root cause of my rosemary’s discontent by considering the adequacy of temperature, soil, light and water conditions in the garden to meet the plants’ needs. It’s highly likely that the rosemary shrubs have been overwatered because they are on the same overhead sprinkling system as the rest of the garden (and the field crops at the farm).
Since it’s impossible to change the watering conditions in the garden right now, I reluctantly made the decision to remove most of the rosemary plants, at least in the Winter’s Tale plot, because they seem to get more water there than in other areas of the garden.
Of course, having optimal growing conditions is important for all plants in the garden, perhaps most especially our vegetables and herbs. Deardorff and Wadsworth previously wrote “What’s Wrong with My Plant?” (2009), but this time they focus on growing healthy organic vegetables in the backyard garden. They note, “Creating an intact, albeit artificial, ecosystem that functions the way a natural ecosystem does just make sense. Nature is the silent partner who makes your garden work.”
To help gardeners work effectively with nature, the authors provide plant portraits of garden vegetables, from artichokes to zucchini. Each portrait describes ideal growing conditions for the plant, as well as its uses in the garden and how to plant seeds or seedlings in the ground or in containers.
The authors emphasize polyculture, in which different kinds of plants are planted together. They state, “This is one of the most important things you can do to keep your plants pest- and disease-free.” Their simple planting advice takes the mystery out of polyculture: “Be sure each plant’s nearest neighbor is different from itself.”
When problems crop up in the vegetable and herb garden, it’s helpful to recognize when they are related to temperature, soil, light and water conditions. Deardorff and Wadsworth provide handy charts that include plant photographs, a description of plant symptoms and a diagnosis of the problem. For example, one entry shows and describes plant leaves that have turned brown at the tips and along the edges. The diagnosis is leaf scorch from insufficient water and hot temperatures.
Organic solutions to address each diagnosis are also presented in the charts. For leaf scorch, the authors suggest ways to manage water more effectively and how to modify the effects of hot temperature with shade cloths and other strategies.
Most pest problems stem from the lack of resiliency of weakened plants to ward off insects and pathogens that are always present in a natural ecosystem. It’s helpful to identify when insects or fungal/bacterial diseases have affected vegetable plants in order to know which solutions will be most effective. Deardorff and Wadsworth include charts with common insect pests and diseases of particular plant families. For example, the book has four pages of charts describing symptoms, diagnoses and solutions for problems with beans and peas in the legume family.
The charts confirmed that my young bean plants are being eaten by beetles, for which the authors suggest using row covers, encouraging beneficial insects and/or applying insecticidal soap to the leaves.
I’m reminded of something interesting I read in Nigel Palmer’s book, “The Regenerative Grower’s Guide to Garden Amendments (2020). He said healthy, robust plants are more effective at photosynthesizing, so they have higher levels of sugar in their tissue. This makes the plants unpalatable to insects. If my bean plants are full of holes from cucumber or flea beetles, it’s a good indication they aren’t photosynthesizing optimally.
And that brings me back to considering which of the four essential factors is lacking in the garden for these bean plants. My guess is they might not be getting enough sunlight. I either have to modify the site, move the bean plants or plan better next year. Fortunately, the beans are in a container, so they can be moved to a sunnier location.
I appreciate the value of a problem-solving approach that addresses root causes of plant problems, as well as secondary issues that come up when growing conditions are less than ideal. By using a two-pronged approach, I could be asking “What’s wrong with my vegetable garden?” a lot less frequently.
Rhonda Nowak is a Rogue Valley gardener, teacher and writer. Email her at Rnowak39@gmail.com. For more about gardening, check out her podcasts and videos at https://mailtribune.com/podcasts/the-literary-gardener.
My garden to-do list this week
In the vegetable beds, this is the last week I direct seed basil, beans, beets, carrots, cucumbers and pumpkins, and the last week I transplant seedlings of melons, tomatoes, peppers, eggplant and celery.
In the flower beds, this is the last week I direct sow or transplant seedlings for summer and fall blooms.
I’m collecting my weeds and other plant debris for fermented plant juice; I’m finding this is an easy-to-make foliar spray and soil drench.
I’ll take pictures of plant problems (particularly in the vegetable beds) and use “What’s Wrong with My Vegetable Garden” to identify, diagnose and resolve issues.