Adjust pH after planting - Ask Extension
I have already planted tomatoes and egg plant,never tested soil,can I adjust soil if needed after planting?
Knowledgebase
Adjust pH after planting #935185
Asked June 12, 2026, 1:23 AM EDT
I have already planted tomatoes and egg plant,never tested soil,can I adjust soil if needed after planting?
Multnomah County Oregon
Expert Response
Thank you for your question. It would be helpful to know more before giving you an answer. Are they planted in potting soil or native (clay) soil? Are the plants in containers? Generally, you shouldn’t try to change the pH without knowing what it is now. What indicates the pH needs to be altered?
Please provide more information so we can advise accurately. Thanks!
Please provide more information so we can advise accurately. Thanks!
hi, i have the egg plants in large pots about 12 in tall, planted in a combination of ordinary garden soil, packaged compost soil, and worm droppings from my worm . Tomatoes planted in raised beds, with composted soil and worm droppings
Thanks! What makes you think you need to change the pH?
i read your blurb in the extension newsletter
Steve Katz
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Aha! Well, there are about a half dozen articles, and they all recommend that you get your soil tested for specific crops before adding anything affecting pH. You can get tests don by the OSO Soil Lab, or A&L Western Labs. Both will give you recommendations on soil additives, if you pay a small fee. Or, you can buy a soil pH meter, or use litmus paper.
Our resources all recommend that you do the testing in the fall so you can add the change agents in time for them to be useful by spring. Without testing now, I suggest that you just add time release fertilizer and enough water to keep the plant "happy". Here's more: https://extension.oregonstate.edu/catalog/em-9027-growing-your-own
I hope this is helpful.
Our resources all recommend that you do the testing in the fall so you can add the change agents in time for them to be useful by spring. Without testing now, I suggest that you just add time release fertilizer and enough water to keep the plant "happy". Here's more: https://extension.oregonstate.edu/catalog/em-9027-growing-your-own
I hope this is helpful.
Thank you so much for the info!
Steve Katz
<personal data hidden>
Say no to plastic
Yes to solar
If not now when
If not me who
Welcome!
