Gardening

Here's why you should be thinning your root vegetables now

I am getting quite a few questions from novice growers, which is great, of course. Let's start with a rolled up discussion of those that pertain to growing vegetables.

First, have you thinned out your veggies yet? I know it is a great thrill to see all those carrots lined up one next to another, but they are not going to develop if you don't thin them out and soon. These root crops need room, at least an inch around. Most crops need room to grow. If you don't know how much room, turn this into a thinking game: You know what they look like when you buy them at the supermarket. Envision mature plants in your garden and thin out accordingly so they can reach that size without impeding their neighbors.

As it turns out, carrots are very heavy mycorrhizae formers. You think the carrot is the root, but actually it is the storage organ and has lots of root hairs. You want them attracting mycorrhizal fungi to form the mycorrhizae. When you pull out the thinnings, you will disturb the soil a bit, so if you have not applied any endomycorrhizal fungi to your patch, now would be a good time. Sprinkle it on, water it in and just let the soil settle back into place. Oh yeah, mulch; carrots love a good mulch.

Beets too, must be thinned, but for another reason as well. Those seeds you planted were really pods and each contains six or so seeds, which must now be plants and should be thinned down to one. You can try and move or replant those you pluck out. They may grow into beets, but you will surely get greens if that is your desire.

I have already mentioned that you need to harvest radish. If you like them enough, plant a new crop. This time plant a few seeds every few days so they don't all ripen at once. You can also plant a new crop of Kohlrabi, and yes, your current crop probably has roots getting to harvestable baseball (not softball) size.

The gamblers amongst us should start some broccoli seeds now for a second set of plants. If we have another warm fall, you will be able to harvest these at the end of September. Take a chance. You can plant these directly in the garden too. No need to start them indoors.

Next, I am getting some cannabis questions. Like tomatoes, cannabis needs room to develop roots. For most types, at least five gallons of soil is needed. If yours is in anything smaller than five gallons of soil, it is time to transplant. And, like carrots, cannabis loves mycorrhizal fungi. In fact, one kind in particular, Rhizophagus irregularis. This is its current name. Old names include Glomus mosseae and Rhizophagus intraradices and Glomus intraradices. Most endomycorrhizal fungi sold contains it. Some only contain it. Sprinkle on roots before your transplant.

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How tall does a cannabis plant get? A couple of readers have been impressed with how large their plants are getting. Look out. Some species can get to 14 feet which is a lot bigger than most plants Alaskans have previously grown, indoors or out! You can pinch them back to make them shorter but bushier, but do it before the middle of July so flowers can develop.  You can also bend back stems providing you don't break them.

What do you feed a cannabis plant? You should be using great compost-type soil along with mycorrhizal fungi. In this case you really don't need to feed your plant — or the microbes that support it — anything. If your plants are not green and healthy, only use organics to perk them up. Low number, soluble organic fertilizers. Again, a handful of compost and some mulch along with compost tea will help.

Finally, I am getting one big question from lots of folks: what to do about dead spruce trees? Well, you know the answer. These will not come back to life. And, the rot has started. These will eventually blow down. If yours is a hazard, it needs to be removed. If you let it fall or remove it, either way, either get rid of it or remove the bark so the downed tree or wood from one can't be a host for more beetles.

Not all of the dead trees are caused by spruce bark beetle attacks. You will notice a pile of sawdust at the base of infested trees if yours has been hit by them. Some die of old age, damage to roots and disease. In any case, don't let a dead tree become a danger tree.

Jeff’s Alaska Garden Calendar

Second Annual Beer in the Garden: July 14, from 6:30-9:30 p.m. If you missed it last year, here's your chance to walk in the Alaska Botanical's beautiful gardens and enjoy the taste of Alaska's finest breweries. Info and ticket purchases at alaskabg.org/event/beer-garden-2/.

Snap peas: Should start to harvest so that the plants will continue to bloom and produce more pods.

Sweep up: If you want to have a good looking landscape, then sweep your driveway, walks and decks to match the look.

Jeff Lowenfels

Jeff Lowenfels has written a weekly gardening column for the ADN for more than 45 years. His columns won the 2022 gold medal at the Garden Communicators International conference. He is the author of a series of books on organic gardening available at Amazon and elsewhere. He co-hosts the "Teaming With Microbes" podcast.

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