Tomato Problems in July: Cheap Fixes That Actually Work
Something happens every July. You walk out to check your tomatoes, feeling pretty good about yourself, and suddenly the plants look like they’ve been through something. Weird faces on the fruit. Brown patches. Leaves curling up like they’re trying to hide from you. And you’re standing there with your coffee going “what did I do wrong?”
Probably nothing. Or, more accurately, the problem happened weeks ago and your plant is just now filing the complaint. Let me walk through the usual suspects.
Catfacing: A Memory of June
Those weirdly puckered, scarred, almost grotesque-looking tomatoes near the bottom of the plant? That’s catfacing. Not a disease. It’s a deformity that happens when temperatures dip below 55°F during flowering, which, if you’re in the Pacific Northwest, describes basically all of June.
The flower petals fuse to the developing fruit during cold spells, and what you end up with is a tomato that looks like it had a rough night. Still edible. Often still delicious. The fix is nothing, because the damage is already done. Next year, wait a little longer before transplanting, or cover your plants on cold nights. Cheap row cover from the hardware store does the job.
Blossom End Rot Coming Back
Here’s the one that trips people up every single year. You see that black leathery patch on the bottom of your tomato, you Google it, and every result says “add calcium.” So you dump lime or eggshells into your soil. And it keeps happening.
The actual issue isn’t a lack of calcium in your soil. It’s that the plant can’t move calcium to the fruit fast enough when water uptake is inconsistent. Calcium travels through the plant via the xylem, basically the plant’s plumbing, and if water flow is erratic, calcium delivery stalls. The fruit pays the price.
Your soil almost certainly has enough calcium. Your watering schedule is the problem. I dumped a whole bag of lime into my bed the first time I dealt with this, which did essentially nothing, so learn from that. Water deeply and consistently, and if you haven’t mulched yet, do it today. Seriously, stop reading and go mulch. Straw, wood chips, shredded leaves, whatever you’ve got. Free is fine. Two to three inches keeps soil moisture from swinging wildly between bone dry and soaked.
Cracking: The Feast After the Famine
Tomato skin grows at one pace. The interior of the fruit grows at whatever pace the water supply dictates. When a dry spell breaks and the plant suddenly gets a big drink, the inside swells faster than the skin can stretch. And the tomato splits.
I lost a lot of really nice tomatoes to cracking before I figured out it wasn’t random. It was always after a dry week followed by rain or a heavy watering. Every time. The fix is the same as BER: straw mulch plus consistent watering. Mulch is doing more work in your tomato bed than any fertilizer you’re buying, and it costs almost nothing if you find a local source.
Leaf Curl: Probably Fine, Honestly
Leaves rolling up tight on themselves look alarming. They look like something is very wrong. Usually they’re just hot and stressed. Tomatoes curl their leaves to reduce surface area and slow transpiration, basically sweating less on a hot day. Physiological leaf roll, they call it. Not a disease. Not a deficiency.
If the curl is only on the lower leaves and the plant is otherwise growing fine, relax. Water it. Maybe rig up some afternoon shade if you can manage it. But if the curl is combined with yellowing, mottled color, or weird growth, that’s a different conversation about possible viral issues. Nine times out of ten in July in Redmond, though, it’s just a hot afternoon. So there’s that.
Late Blight: The One You Actually Need to Worry About
Okay, this one is real and it moves fast. Late blight is caused by Phytophthora infestans, the same pathogen that triggered the Irish Potato Famine, which is a fun fact that will ruin your appetite for tomatoes if you think about it too long.
What to look for: greasy, water-soaked brown patches on the leaves and stems that spread quickly. In damp weather, check the underside of affected leaves for white fuzzy growth. That’s the sporulating mycelium and it means the infection is active and spreading. Our wet PNW springs set this up perfectly, and by July you’ll know if it took hold.
If you see it, act the same day. Remove and bag every infected leaf and stem. Do not compost it. Do not leave it on the ground. Bag it and get it in the trash. If it’s widespread, the plant might need to come out entirely. I know that’s brutal mid-season, but late blight can spread to neighboring plants and your neighbor’s garden, and nobody wants that conversation.
Copper fungicide spray can help slow it down before it gets bad. Reasonably cheap at most garden centers, I picked some up at Swansons last year for around $8.47. Not a cure, but it buys time.
Most Tomato Panic Is a Watering Pattern Problem
Before you buy anything, before you amend anything, look at how you’ve been watering. Catfacing aside, that’s a temperature thing and it’s behind you now. But the rest of this list connects back to inconsistent moisture. BER, cracking, leaf curl, even susceptibility to disease when plants are stressed.
Drip irrigation sounds fancy but you can set up a basic system for under twenty dollars and a Saturday afternoon. Or just water deeply every few days instead of shallowly every day. Mulch the bed. Done. You’ve just solved about 80% of mid-season tomato problems without spending anything you didn’t already have.
The plants are telling you something. Most of the time they’re saying “water me better.” Lettuce not overthink it.
Photo by Kylli Kittus on Unsplash
