Average Last Frost

Bear with me, this is going to be a wordy post. After a full season having a vegetable garden and dealing with one of the crummiest Seattle summers in recent memory, we are spending some time this winter/early spring to do a debrief of how things went in order to determine a strategy for this coming growing season. This post is mostly to sort thoughts and make some plans, so you all might find it completely boring.

We haven’t finalized the list of fruits and veggies we want to grow in 2011, and we need to look at how things went in 2010 to fully decide. Its nice to spend some time thinking of what will pop out of the ground when the sun shines!

Here’s a rundown of last years hits and misses:

1. Raspberries. Awful. We bought some starter plants and waited too long to get in the ground. Not a single leaf grew and we replaced the bed with lettuce.

2. Strawberries. We bought some small starts from the farmer’s market. No fruit the first year, but we think we have successfully over wintered these plants and will get more out of them this season.

3. Snap Peas. These were quite successful and I think we’ll plant more this year. We only planted about 6 seeds last year and our trellis could have been more dense. Maybe a second trellis for a couple other varieties this year?

4. Tomatoes. What a valiant effort. We started them early indoors, but got a grow light on them too late, after they were already spindly little things. We put them outside, and they grew to a significant height but didn’t produce more fruit. Problems were: crappy Seattle summer, not enough light in the backyard, too many plants were overcrowded. This year, we’re pruning the heck out of our backyard to get some more light in there, and we’ll go for quality over quantity in terms of plants.

5. Beets. See above overcrowding. We planted beets right next to the tomatoes, and I think the heavy eating tomato plants sucked all the nutrients out of the soil. The beets didn’t really develop any sizeable roots and we had some problems later in the summer with leaf miners.

6. Leeks. Got muched by Ricky Racoon. All the way down to ground level. Not even worth mentioning.

7. Onions and Shallots. These were both very successful for us and we’ll probably plant a full bed again. We’ve been eating them all winter and they keep so nicely you can never have too many.

8. Cucumbers. Our cucumber crop was great, despite early worries and the crummy weather. Hopefully with a better summer on the horizon we can be even more successful.

9. Potatoes. We had a semi-decent crop of red potatoes. Saw a compact growing trick on the Fiber Farm blog the other day and we’ll be trying this to save some space and get a better harvest.

10. Lettuce, Arugula, Endive. All semi-successful. Will do again, since you can’t go too wrong with the lettuce mixes.

11. Fall Crops: Cabbage, Kale, Chard, Brussel Sprouts, Spinach. Pretty much a big bummer. The Kale did alright, the others, not so much. We had issues with cabbage loopers, and also some very cold temperatures in November which cut off the plants before harvesting.

Overall, the lessons learned ares:

A. We got a start too early last year on some crops and they didn’t develop robust stems and root systems and weren’t as healthy as they could be. PATIENCE is the name of the game (something I constantly struggle with).

B. We need more sun in our garden. The south side of our property is heavily shaded and we need to spend some time thinning that out to get more significant light back there in the spring and summer.

C. Pay better attention to fertilizing. Some of these veggies are hungry little guys and I think we could have more regularly fed them (other than water, of course).

D. Find a solution for pests. This goes for squirrels, racoons, and buggies. We want to keep the garden organic as possible (no one wants to eat or pay for chemicals), but there needs to be a more dedicated effort. Last year it was mostly called hope they stay away. I am going to do some research on companion planting and organic pest solutions to give us a better arsenal.

Whew! We’ll likely be buying some seeds this week or next once we finalize our list, and so I thought the first step would be to address lesson “A” above: Research more on timing.

First, I went to Ed Hume Seeds to check for average last frost information since they are a site dedicated to Pacific Northwest Gardening. The dates they give for Seattle metro are: Average Last Frost (determined from last year): March 22. Safe Date: April 15th. We’re having a less severe winter than “they” predicted, however we had freezing temps several days last week, so we’re not out of the clear yet. For talking purposes we can use April 1st as our target date, and if we have to hold off on planting a week after that, fine.

Next, I went to a link I found last fall that makes a custom Spring Planting Calendar based on date of last frost. You can input whatever your last frost date is, and it will give you a list of milestone dates before and after to keep you on track. Its so handy! So, I put in 4/1 as our average last frost and here’s the outcome:

Eep! Looks like we’re a little bit behind on sowing cool weather crops (spring kale, broccoli, chard, onions, etc.). We’ve been eating a lot of these all winter by virtue of our CSA, so I don’t know how many of these we’ll be pursuing again until next fall. Plus, until we can figure out the cabbage worm problem, they’re a little frustrating for us. Its also about time to sow our tomato seeds indoors (which means we weren’t THAT far off last year).

There is a list of other online calendars in her original post, including one personalized by zip code. The Farmers Almanac link lists the average last frost for Seattle as March 10, but after last year, I’m pretty skeptical of starting that early.

The last question I have for this spring, which will go along with what we decide to plant is how to know whether leftover seeds from last year are viable. There are a couple seed germination tests that sound easy enough, but if we want to get new seeds we need to do it soon, so I am going to look at our seeds and see which might be up for the test and which we will re-buy.

So far the short list is as follows, we’ll update you with what we finally decide to buy and in which form (seed or plant):

Tomato (We might buy starter plants instead of growing from seed)

Lettuce Varieties (Including spinach, arugula, endive, and who knows what else?)

Bok Choy (We have grown to love via our CSA this winter)

Onions

Shallots

Potatoes (Varieties TBD)

Strawberries (overwintered; already in the ground)

Cucumber

Beans and Peas (Varieties TBD)

Beets

Raspberries or Blueberries

Herbs (some have overwintered: rosemary, thyme, need to re-plant basil)

Pumpkins

Anyone have suggestions for veggies we should add or eliminate from this list? Right now its pretty heavy on an August/September harvest so it might be nice to add something a bit earlier.

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5 thoughts on “Average Last Frost

  1. I think the tomato date that tool came up with is way too early. I personally wouldn’t put tomatoes outside until after Mother’s Day. In fact, we plan to buy ours from a plant sale in May at Orca K-8 garden. If they get cold they get stunted and never seem to produce well. They also get all watery from spring rains.

    Squash I would do around the same time to avoid powdery mildew, especially since you have such low light. Pumpkins you can direct sow, but zucchini does better with starts.

    Dave’s mom suggested to us starting your peas indoors because once they are growing they can take the cold, but they won’t germinate as well if it is still really cold.

    Butter lettuce works wonderfully for us! We also really like growing sunflowers and zucchini. Carrots were fun, but we struggle with root vegetables getting eaten up by bugs.

    Just my two cents…yay for gardening!

    P.S. – Tilth has nice month-by-month to do lists!

  2. Tomatoes after Mother’s Day is the rule in NJ, too! I was brought up with that “gardner gem” recited by my Father, Danielle’s Grandpa. I also buy some nice varieties from a local greenhouse that are acclimated properly to the weather, via a properly run greenhouse run by a local family, Coppola’s, a true cottage business. The $5 I spend on each plant is well worth the hardiness. They have a huge variety of Rutger’s plants and Heirlooms!!!! I also plant many of the plants in huge pots. I can really move them around and gain the sunshine hours they need. The winner in my partly sunny NJ garden is the Lemon Boy!!!!! What a fantastic heirloom.

    Pole Beans were a favorite of Danielle’s when she was young. Try them. Take three pieces of wood and tie them on the top as if you were making a “Teepee”. Plant 6 pole bean seeds around the structure. Watch them grow and produce many beans in a small area! We used to plant them in our garden every summer. Danielle’s rabbit, Cottontail ate the leaves and often dwarfed the plant!

  3. This is only my second year gardening. So i don’t have much to add. I live in Seattle on the north side of Greenlake. My whole family is pretty involved with gardening though. My mom being the main green thumb. I remember being a little kid in Georgia on vacation and seeing huge tomato plants. So I figure they can withstand a little more heat and humidity. I should add that I grow everything in pots on my patio on the south side of the house. I had a pretty good harvest of tomatoes last summer. More than I could eat from four fairly modest plants. two smaller cherry varieties. and two bigger types I can’t remember. I kept them inside till April 1st, then when outside I kept them wrapped in plastic until the end of June. There was significant difference to the plants that my mom planted, but didn’t cover. She lives on the south side of Green lake. The were also planted on the south side of the house and had good sun. I also had good luck with broccoli and potatoes. I just stumbled across your site looking for last frost info. This post is really great! thanks! Matt

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