There are different ideas about when to start seeds indoors. Some gardeners like to start very early, and others like ourselves follow a later indoor seed-starting schedule. We have good reasons for that and over years good experiences with it too. Even though we do understand that it might be hard to wait. Personally, we would recommend growing an indoor garden, or at least some microgreens instead of starting seeds for the summer garden so early. In this post, we want to take a look at when and why we start seeds following this schedule. Plus you can print yourself a schedule to follow with your exact dates.
The Seed Starting Schedule
Seedlings grow best when planted out small. It does not disturb the roots so much and it is much easier to plant. Some plants like lettuce only need about 3 weeks from seed to planting out.
The indoor seed-starting schedule we follow is from the All New Square Foot Gardening book. It is a great chart showing the seed starting date as well as the planting out date.
The first is the picture without the dates, it is for you to make your own if your last frost date is different from ours. Write your dates into the schedule counting back from your last frost day.
If your last frost dates are the same as ours, choose the second picture with the dates on it.
It is free printable for you. 🙂
To print out the schedule, click on one of the pictures below to make it full screen by clicking with your mouse on the picture. Now you can print it or save it on your device.
Starting time for cold weather crops
Following this schedule, you will be starting cold-weather crop plants like brassicas and onions first. The reason is that they also can be planted out first. As we have noticed before, the schedule does not just give you a starting time, but also a plant-out time.
The advantage of planting cold-weather crops out earlier is to prolong your growing season, but also cold weather crops do like it cool and often will grow better in cooler conditions. Also, the cabbage butterflies tend to come out in late summer, so harvesting the broccoli before that is a win-win.
Of course, not all plants we might grow are on the chart, only the main crops from a plant family. So if you also grow Brussels sprouts and shallots, start them with other brassicas or onions.
Starting time for summer crops
Summer crop plants like it bright and warm. In our area, the daylight from October 28 to February 14 is below 10 hours.
If you start your seeds before or right at the edge of the 10 hour day, they will grow very slowly and become spindly. Spindly and weak seedlings, for the most part, are no good. They do recover after being transplanted, but that takes time, precious time that a short growing season gardener does not have.
To avoid having spindly seedlings you can use a grow light, but then your seedlings will grow fast and result in overgrown plants. In our experience, it is much better to wait till spring progresses and there is enough natural sunlight and warmth. And even if you use grow light, it is still better to wait.
The focus of every plant is to bring forth seeds. If the plant is healthy and the growing conditions are right, the plant will concentrate on getting a good root system, leaves, flowers, and then fruit – and lots of it. However, if a seedling sits for too long in a small pot, it gives the plant the signal that it can’t get any better roots nor leaves. All it wants to do now is to produce some fruit before it perishes.
As a beginner gardener, you might be excited to see the first flowers and even fruit on your seedling, thinking that you really got a head start. But that is not true. What you got is a desperate plant that has put all its energy into producing that one fruit. It will not have the energy to produce much more than that.
Starting summer crop seeds 6-8 weeks before planting them out, is much better. If you are not sure about the weather, start at 6 weeks; in this case, if you have to wait longer, the seedling will not overgrow.
Seedlings that are at a stage where they are almost putting forth buds are just right. The roots are still young and will adapt easily to the new location, and the plant is ready to grow and produce a lot of fruit. Read more about when to start tomatoes here.
By the way, you can start a plant or two early and give it the best conditions possible indoors. This way you can have really early tomatoes. Read more about growing tomatoes indoors.
If you grow ground cherries they need to be started earlier, along with broccoli would be a good time, simply because they need longer to germinate.
Peppers and eggplants are particularly heat-loving, eggplants even more than peppers. Do not rush planting them out, making sure all danger of frost is over.
Starting time for cucumbers family plants
Cucurbits family plants are squash, zucchini, cucumber, pumpkin, etc. Most of them are very fast-growing plants, and they too like it summery bright and warm. Most of them also don’t care much about being transplanted. If you want or need to start them indoors, give them a bigger pot (4-6inch), and do not start too early.
Personally, we start spaghetti squash and winter squash indoors and wait to plant them out a week or two after the first frost. Zucchini we mostly just start in the garden directly, even though during cool springs (and we never know ahead of time what spring will be like) starting indoors is a better idea. Cucumbers can be sprouted to give them a head start and planted directly into the garden or greenhouse.
Starting time for growing in a greenhouse
If you grow a greenhouse garden, you can adjust the seed starting times accordingly. It will take some practice to see how your greenhouse reacts to frost. Remember that a simple plastic poly gives you only about 3 degrees at night. If you don’t use any heat source, you might want to wait with heat-loving plants till the last frost day, just like whiteout a greenhouse.
In our Geodesic Dome greenhouse, we use a car radiator to heat and cool the room. This allows us to plant about two weeks earlier than the last frost day (still watching the weather though).
I hope this helps you to understand spring indoor seed-starting schedule times better.
Do you like to start your plants from seeds or would you rather buy seedlings?