Maintenance Tips
Each season brings different things to do in your garden. Some tasks are solely based on appearance and some are smart practices. Here are some tips!
Grasses! Since you left your grasses up as winter interest, February will be the time to cut them down. If you look into the crown of the grass, you will see the new spears hiding. You can cut the old stems down to this height. HOWEVER if you’d like to promote habitat for native pollinators and other invertebrates, don’t take away their wintering homes just yet! The bugs will need close to 60-degree temps to be on their way: mid to late March.
Leave some leaf litter until March for habitat too.
Any winter kill on perennials that you didn't cut down in the fall, you can do now, but do check for eggs or larva before discarding. You can always tuck these stems behind a shrub or in a corner.
Aphids: Ah, the time for the puckering of stem tips and leaves, and the falling of aphid dew on our cars and windows! Aphids just disfigure growth— not kill. Aphid infestation does look pretty gross though. Topical insecticides kill them, but then what will the ladybugs eat? Systemic insecticides fill the plant's vascular system so that anything that feeds on the plant dies. This can carry over to whoever then eats the aphids, like ladybugs. Possibly poisoning many in the food chain. Since aphid damage is mostly superficial and seasonal, AND feeds Lady bugs, you can just let it happen….. or hose down the plant with a steady stream of water ever couple of days, knocking the aphids off.
Weeds: Weeds can be tricky. Distinguishing between annual and perennial ones can help with your plan of attack and success. Rule of thumb for both: don't let them go to seed! The more seed which is dropped back down into your beds, the more weed babies you will have. The less cultivation of the soil, the better. You don't want to cultivate more weed seeds into the soil. Keeping in mind that seeds can exist dormant in the soil for many years, it will take at least two years to notice a difference. Persevere! We have cleaned properties of goathead by being fastidious in pulling it out before it went to seed.
Annuals: Come up from SEED, germinate, grow, flower, die
Some common annual weeds: cheat grass, bur buttercup, medusa head grass, tumble mustard, koshia, cereal rye grass, goathead, etc.
Annual weed control: Pulling is labor-intensive but quickly ends the weed's life. Horticultural vinegar can be used effectively in cooler temperatures compared to other herbicides. Spraying needs to be done on a calm day when drift won't damage surrounding plants. Other herbicides are useful but work better on warmer, calm, dry days.
Perennials: Come up from the over-wintering ROOTS, grow, flower, go dormant
Some common perennial weeds: Canadian thistle, alfalfa, whitetop, skeleton weed, bindweed, etc.
Perennial weed control: If pulling out, perennial weed roots need to be completely extracted for the plant to die. Horticultural vinegar can kill the surface leaves, but the weed can re-sprout. Other herbicides are designed to be absorbed by the plant and travel to the roots to kill it completely. Smothering it another option, keeping sunlight and moisture from the weed.
As we all know, it stops raining in the summer. We are painfully aware of this as we look up into the foothills and see the invasive grasses browning out. The photo above shows what a client's hill looked like (her neighbor's hill in the background) 3 years ago. Now her hill is full of native plants and is more fire-wise.
Summer dormancy: In the heat of the summer, many natives go into dormancy. Many clients want to water extra in the summer, but don't realize that they can actually harm their plants. Dormancy is a natural part of our native plants' cycle and just means that their growth stops. We wouldn’t water a daffodil after it blooms and goes dormant and so similarly not for our native Arrowleaf Balsamroot.
Maintenance: Some plants will have finished blooming. If you want to deadhead, consider these points:
If you are deadheading penstemon: Penstemon tend to be short-lived, so you need to let the seed mature and drop so that the babies will replace any plants that die.
If you have a small grouping that you want to beef up: after flowering, let those seeds mature and then disperse them to increase the plant's population.
However, in a garden setting, if you have a plant which has been having a lot of unwanted volunteers, you can control its propagation by deadheading before the seeds mature.
In a foothills setting, with no supplemental water, there is enough seed predation by insects and seedling death that deadheading is not required.
As the leaves start to fall off the trees, we begin to notice what is left. This is where the term 'winter interest' comes into play. It can be great to clean up all the leaves and tidy up your garden before winter, but here are a few things to consider:
Leave your grasses standing: Along with the grass seedheads becoming your winter interest, the stems of the grasses can be over-wintering habitat for some bug species (see Little Neighbors section).
Some perennials provide food for wildlife, so don't deadhead them! A good example of this is Echinacea, or coneflower, seeds, which finches will eat throughout the winter.
Leaf litter: Leaves make great compost. Some people leave leaves in the garden to compost over the winter. But too many leaves on top of an evergreen/gray perennials can cause rot and damage it.
In the fall, it is normal for some evergreens to take on a different color, which will last through the winter, like Oregon Grape and Kinnikkinnik below.