Skip to main Content
Gardening

They might be pretty flowers, but these weeds should have no place in your Alaska yard or garden

  • Author: Jeff Lowenfels
    | Alaska gardening
  • Updated: July 2
  • Published July 2

Orange hawkweeds grow in Girdwood on Thursday, June 16, 2016. (Marc Lester / ADN)

It is summer and readers have all manner of questions. Where to begin?

First, are you finding plants on your property with pretty, red to orange, “dandelion-like” flowers? Several fellow readers have. You may be spotting them along the road or on trails as you walk. The flowers are actually smaller than a dandelion, on a longer, hairy stalk, and each stalk usually supports several flowers.

This is hawkweed, Hieracium. Look it up on the internet, even if you don’t have it. There is a good chance you will. I found some this year on a path in the woods. Where did it come from? Is this Alaska’s next noxious invasive?

Dig up hawkweed plants. They have shallow roots. Do not be fooled by its startling, flame red or orange flower, nor the desirable, impenetrable mat the plants can create. It is the devil’s spawn in our climate.

Next, there is a second dandelion-ish looking weed causing people to wonder if global warming is creating giant plants. Perennial sow thistle (Sonchus arvensis) is often called “giant dandelion,” as its flowers are usually borne on tall stems, up to 3 feet or so. You will see them along roads where they are really proliferating and sometimes in your lawn. Unfortunately, these weeds have extremely deep and extensive roots, and if you pull the plant up, parts remain in the soil. Each leftover root section then grows into a new plant.

The trick to control of sow thistle is to keep at it but, instead of trying to pull it up, cut the plant off above ground at its base. If it grows back, and it will, cut it again. Persistence and you will beat it. Since at first they grow individually, take care of any you find on your property, ASAP. Above all, do not let it flower, and if it does, do not let these go to seeds.

Closeup of a bright yellow flower sow thistle or Sonchus arvensis. (Getty)

Next, yes, this is the week to thin out vegetable seedlings and yes, you can eat them. Beets, carrots, lettuces, radish and possibly other row crops you put in are getting crowded. If you don’t thin them out, you are likely to end up with miniature veggies. Plants need room to grow. How much? You know what the final product is going to look like; give it enough room to reach that size with a couple of inches to spare.

Some plants you thin out can be transplanted elsewhere. Lettuces, for example. Carrots and beets, on the other hand, are not easy to transplant successfully.

A few lilac questions answered. Yes, the time to prune lilacs is immediately after or while they are in flower. You can transplant lilacs all season long. Use native soil. If you only have flowers on the tops of your plants, you didn’t use enough Plantskydd last fall, as this is a classic sign of moose browsing.

To compound our aphid problem, this week is going to be warmer than most. Make sure you water your lawns, which will water your trees and shrubs. Your gardens, too, will need water. And don‘t forget your raspberry patch. This is not a good time for the plants there to be dry as they are setting flowers and growing fruit.

What to do with those spring daffodils and tulips? They probably won’t perform again next year. Just leave them. Who knows? A few may make it to next year. Instead, spend time staking delphiniums and peonies so they are not destroyed when it rains once they are in full flower

Finally, I nag about weeding. A little bit of work now will save your vegetables and annuals from the competition. Butter and eggs are really ripe for pulling right now. They will start forming seeds in a few weeks so get them. And chickweed just continues right along. Pull it and remove it from the garden.

Jeff’s Alaska garden calendar

Fourth of July: Great time to garden instead of partying! Have a great one!

Alaska Botanical Garden: Trails are open and the gardens are beautiful. Check out alaskabg.org for the latest news. Thursdays are for picnics in the garden, 6-8 p.m. The nursery is open.

Water: How much? At least 1 inch per week between you and Mother Nature.

Greenhouses: Leave the doors open to encourage insect pollination. Stake tomatoes and cucumbers

[Because of a high volume of comments requiring moderation, we are temporarily disabling comments on many of our articles so editors can focus on the coronavirus crisis and other coverage. We invite you to write a letter to the editor or reach out directly if you’d like to communicate with us about a particular article. Thanks.]

Sponsored