Planning Your Planting Calendar: How to Figure Out What to Plant & When

planting calendar

If all you knew about growing vegetables was learned from the back of one of those seed packets you find in big home DIY department stores, you might be tempted to think there was only one possible growing season. It would start after the last chance of frost, continue through the summer, and end in the early fall.

However, if those plants failed, you’d be stuck thinking about what you did wrong for an entire year. This is where most people come to the wrong conclusion: “I have a black thumb.” Also, your plants might not fail at all but never produce any fruit or harvest even with good pollination.

Maximize Your Growing Time… not just Space

For those of us attempting to do urban/suburban farming in a small amount of space, it’s important to maximize the productivity of our land. This can be done by optimizing our space (growing vertically, utilizing different layers, etc.), but quite often we forget to think about optimizing our time.

The year is a full 365.25 days long, so if we want to increase the amount of food we can grow as well as provide fresh food year-round, we also have to think more deeply about the best time to grow our plants.

“Since plants have tuned themselves for specific triggers and sensory events, they will grow at a much faster speed when they’ve determined their optimal time to grow.”

Plants have evolved in specific environments so they have adapted to flourish in those environments by tuning their senses. We tend to view plants as simple organisms, but as we continue to learn more about biochemical cellular mechanisms it’s apparent that even a basic cell’s dynamics are far more sophisticated than anything we’ve constructed ourselves.

Being constantly reminded of how miraculous and sophisticated nature is giving me a greater appreciation of life in general and helps me to link gardening to something deeper beyond the immediate need to feed myself (although that’s important too 🙂 ).

What is your Plant’s Preferred Temperature Range?

Some of the time-dependent environmental conditions that plants have been found to be sensitive to include the day length, temperature, and weather patterns. Since plants have tuned themselves for specific triggers and sensory events, they will grow at a much faster speed when they’ve determined their optimal time to grow. Taking advantage of that knowledge will help us maximize the growth curve of the plant. Luckily for many common crops, it’s quite easy to find published optimal temperature ranges (for example, temperature range chart).

You can also find online charts of average temperatures by day/month (for those of you in the US, weather.com has monthly average temperature charts by zip code). If you match up the plant’s preferred temperature range with the average temperature curve for your growing location and include the number of days estimated till harvest for that plant, you can figure out the best time to grow that plant.


Here is an example using snow peas, with an average time to harvest of 70 days and temperature range of 40-85 F. For Virgina, mapping the low and high temperature ranges gives the range of possible growing dates.

What is Photoperiodism?

The other major environmental factor that’s easy for us to factor into our growing calculations is the amount of light the plant is looking to receive (photoperiodism), with plants falling into 3 categories (long-day, day-neutral, and short-day).

Long-day varieties are looking for at least 12 hours of sunlight in order to bloom (flower, grow big bulbs, etc.).

Short-day varieties are looking for less than 12 hours of sunlight while day-neutral plants don’t care either way.

Armed with information about the amount of light the plant wants, we can go back to our optimal days of growth and tweak the starting/ending date based on the day length. Determine your location’s latitude,(for instance, In Northern VA, we are 39 degrees N) then take your start and end dates for your target plant and look up the day length on those days using these great latitude daylength charts.

If we find the day lengths are wrong for the start or the end date, you can shift the dates accordingly. It’s more important to make sure the end date meets the day-length requirements in order to ensure a proper harvest.

Continuing the previous example, Virginia has to wait till April 1 for over 12 hours of light. We shift our original date range slightly to the right to account for the day length and maximize our chance of getting our peas germinated.

This is probably already enough to digest in one session, so stay tuned next week for “How to Use Crop Rotations & Succession Planning” where I go into how to rotate your plants in your garden for maximum yields and translate all of our start and end dates into a simple, cohesive strategy for the whole year.

Dig Deeper

Ready to start your own planting calendar? This year we have a Garden Planner for Cold-Weather Crops that we made specifically for Growing Zone 7. However, it comes with a blank template that you can fill in with your own crops. Click the image below to learn more.


Comments 5

  1. Pingback: Becoming a Garden Ninja! (Planting Calendar Part II) | Permaculture Gardens

  2. Pingback: Extending Your Vegetable Garden Into The Fall - Permaculture Gardens

  3. I find all your articles very helpful. I don’t own my own place but I have a great landlord who allows me to garden in a small area that I soley take care of. This year my children bought me a small porch size greenhouse and with that I started some early potatoes which have been growing great for the last 3 weeks. I’m excited to see what they yield. In my raised beds I have implemented quite a few things I have learned through you. I was overwhelmed with all that I harvested last year and I always reuse seeds from what I’ve harvested. Thank you

    1. Post

      So great to hear about your cute garden and potatoes! Dave has a technique called “hilling” the potatoes and I will ask him to explain it more for you below. “Hilling” which is basically mulching the potato plant even more as it grows bigger will give you a bigger potato harvest than not hilling. Just watch this space for his reply, Martha and keep on growing!

    2. Post

      This is David. Sorry I didn’t get back to your comment until now. I can share what we’ve learned about potatoes and hopefully it helps you with getting a good size harvest. Through trial and error, we’ve found that potatoes prefer cool weather (50-75 degrees) so you definitely want to grow them in the spring or fall (although we’ve had more luck in the spring). Potatoes that are doing well will put on a lot of leafy growth and will start flowering. You definitely want to wait to harvest the potatoes until well after they’ve flowered. Ideally, you want to wait about 3-4 weeks after the top of the plants have completely died off, since the tubers will continue to grow in the soil. I did a trial of 8 heirloom varieties of potatoes last year, and found a huge difference in the yield produced by different varieties, so it definitely is worth finding out what works in your area (I recommend mainepotatolady.com as a source for experimentation). The result of our trials last year was that Pinto Gold and Red Adirondack produced at least 3-4 times more potatoes than the other varieties we tried (we are in northern virginia so it might be different somewhere else).

      “Hilling” potatoes is a laborious process where you continue to mound soil over the leafy growth of the potato every time it reaches 6 inches in height. The idea is that the potato plant gets fooled into thinking it’s not time to flower yet, and will produce tubers all the way up the stem as you mound the soil. I have found that hilling potatoes with soil is way too much effort and doesn’t impact things that much, so this year, I’m trying a method I discovered called the Ruth Stout hay method (https://www.goveganic.net/article182.html). It involves just dumping a huge bail of hay (ideally spoiled) over your potatoes, some 6-12 inches thick. This apparently is just as effective as hilling, but is much cheaper and involves less effort. I would love to hear how it goes for you, Martha, and see any photos of your harvests.

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