never fert a stressed plant ...

and if you just moved them.. it sounds.. more like transplant shock ... increase PROPER WATERING ...

it is my position.. that if you have a decent organic soil ... you NEVER need to fert ... that is the soils job ... you would be just as far ahead.. adding a nice layer of compost every year .. and letting ma nature take care of it all ...

that said.. and presuming they are NOT recent transplants ... a LITTLE of this or that never hurts ...

too many peeps.. especially the noob's .. think their plants are children.. and need to be fed ... they arent.. and they dont.. given decent soil ...

my 5 acres is mineral sand ... one of the least organic soil types there are .... i do not fertilize ... 99% of plants do NOT care ... [and those that do.. die.. and i am done with them.. lol] ...

so dont fall into this marketing scam.. that you need to buy tons of 'food' for your plants ...

ken

psd: the remaining 1% are plants that show some decline ... and i fert them lightly ... and eventually they die.. and i find out.. they had other problems.. and it wasnt a food issue anyway ....

Ditto pretty much everything Ken said--I fertilize nothing and water little else aside from a very few things like astilbe & hydrangea and then only during severe dry periods. Both appear to thrive on neglect even when they don't look their best. If I do fertilize, I use organic seaweed extract or fish emulsion. If things are planted in healthy soil with the proper light & amounts of water they need, it's been my experience they seldom need any assistance from the gardener other than to enjoy them.

Salvia hasn't been a strong grower for me but given the fact so many other perennials have thrived, I decided it was my soil and not my own skill that was at fault. That old saying--if it ain't broke, don't fix it--applies to gardening as well as other subjects. Keep in mind also that perennials are living organisms that will have good years and bad years based on multiple factors--rainfall, temperatures, changing shade patterns, etc. Last year my Lenten roses/Hellebores produced a mere handful of blooms. This year I lost count of the number of flowers on each plant. As with many things, take the good in some years but expect the not-so-good in others.

Excellent advice from both Ken and Garden weed. I couldn't have said it better myself. I would make sure your plants are properly mulched with some organic substance that will prevent loss of moisture as well as dramatic shifts in soil temperature. Mulch is also the best weed prevention you can find.

Martha

Ditto what Martha said vis a vis mulch but I would add a note that layering corrugated cardboard under the mulch works a whole lot more effectively than mulch alone. I initially went with the mulch alone approach but quickly discovered adding the cardboard produced far more satisfactory & longer-term results.

Ditto to everyone, lol, and I just wanted to add that if you are working in an established bed with not a whole lot of room between plants, layers of newspapers will be easier to put down under the mulch than cardboard. You can fold the paper to fit the spots between perennials. I usually do at least 6 to 8 sheets thick. Just be sure to leave room around the base of the perennials.

Dee