Seed starting is fun, challenging, and usually less expensive than buying plant starts from a store. You can grow whatever variety you want, of whatever you want, and have access to a wealth of heritage, heirloom, and open pollinated plant varieties. Seed starting is also an epic way to get kids involved in gardening magic.
I like seed starting because I can grow any heirloom or heritage variety that I can get my hands on. Instead of being confined to about five hybridized tomato varieties, I have access to hundreds of heritage ones. Instead of being confined to a few pepper options, I have access to dozens of sweet, hot, and even miniature varieties. Learning to start your own seeds and seedlings is the main way to access a massive abundance of genetically diverse, visually interesting, and exceptionally tasty garden plants.
Choosing Seeds for Starting:
If you might be interested in saving your own seeds for peppers, or saving tomato seeds, chose heritage or heirloom varieties. These types of seeds have been growing true to themselves for generations, and will continue to produce seeds that are true-to-type. Tomatoes from the store, and most tomato starts from the grocery store or average nursery will be hybrids, and their seed will revert back to one of the parent strains IF you try to save seeds. Some nurseries do carry a few heritage varieties, so you may be able to find a “yellow pear” or maybe a “Cherokee” tomato, which will let you save true seeds even from a nursery plant start.
Tomatoes are self fertile, so you can grow multiple varieties with minimal cross pollination, and save seeds for all of them. This is one reason I love looking for and buying heirloom tomatoes, if I like them it’s easy to save seed for next year.
Other seeds to start indoors include celery, peppers, watermelon, gourds, and cucumbers. Some people will also start corn, beans, and sometimes peas. Flowers to start early can include marigolds, zinnias, cosmos, and summer bulbs like gladiolas and dahlias.
Seed Starting Equipment:
A grow light is essential for starting seeds indoors. It helps keep the young plants compact, and lets you control growth. A full spectrum LED bulb will work, or basic fluorescent shop lights. If you intend to start a lot of seeds, or do it for several years, then investing in an LED grow light can be helpful. You can also use LED grow lights to grow low-growing crops, indoors, during the winter, like microgreens, or lettuce.
A heat mat is necessary for starting any heat loving plants. These include peppers and tomatoes. Celery can be started without a heat lamp, but does need to be started before peppers, which should be started about two weeks before tomatoes.
A seedling tray is nice, but not essential. Avoid coconut coir pots, and peat pots if you are new to seed starting. While these pots are biodegradable, they also dry out faster and are prone to mold. For simplicity, start with a heavy duty plastic seedling tray. You can also use up-cycled and recycled plastic containers, if you’d prefer.
Pots can be nearly anything that will hold soil and moisture. Some people form newspaper into biodegradable pots, others cut down cardboard toilet role tubes, and paper towel tubes. These work well inside larger plastic containers that help hold in moisture, but they can be prone to drying out and prone to mold. A lot of people use plastic party cups, water cups, and even recycle single serving and larger yogurt containers for seedlings. I’m currently using a combination of yogurt containers, small pots from the dollar store, and used paper coffee cups.
Seed starting mix or regular potting soil for your seeds to grow in. I prefer using a fairly light, organic, potting mix so it helps me avoid having to re-pot seedlings too quickly. If you use seed starting mix, be aware that in between the first set of true leaves appear, and the second set, the plants will need to be re-potted or they will run low on nutrients in the seed starting mix.
Tools are the final piece of the seed starting puzzle. You don’t need fancy tools, a butterknife and a spoon will work for seed starting, and for replanting most seedlings. If working with very small seedlings, a metal child’s spoon may work better than an adult sized metal spoon. This year I chose to pick up an inexpensive set of “indoor plant” care tools, a mini sized trowel, spade, and cultivator. I found the miniature sized spade and trowel to be a lot more versatile than the kitchen utensils for re-potting seeds that just had their seed leaves (cotyledons) or were barely getting their first true leaves.
Getting Started The Ninja Way:
Start by figuring out your last frost date, for Zone five, my last frost date is about mid-May. So, for many people in this area May long weekend is the week to plant seedlings and frost sensitive seeds outdoors.
The earliest starts of the spring are started 10-12 weeks before the last frost date. These include celery, lavender, and rosemary. Rosemary is not frost hardy, and should be planned as an outdoor planter plant for summer, and an indoor potted plant for winter.
At 8 to 10 weeks before the last frost date, start peppers, thyme, sage, and other slow but warm growing plants.
At 4-6 weeks before the last frost date. Tomatoes, marigolds, zinnias, cosmos, basil, sage, parsley, cabbage, cauliflower, and broccoli can be started. Plant to re-pot tomatoes two or three times before planting out.
In between 6 weeks and 4 weeks before the last frost date is the best time to plant peas, poppies, lettuce, kale, beets, carrots, and radishes directly in the ground in your garden.
About four weeks before the last frost date (in Zone five) you can start cucumbers, eggplant, melon, corn, and gourds, indoors.
Direct sow pumpkins, squash, corn, beans, and succession plantings of cucumbers and eggplant, one to three weeks after the last frost date.
Hardening Off:
All indoor started plants should be hardened off in the two weeks before you plan to plant them outdoors.
Hardening off is the gradual process of getting indoor plants accustomed to outdoor conditions including wind, rain, sun, and generally “real life.”
Start with one hour, and place plants in dappled shade or a shaded area that is exposed to gentle breezes.
The second day, plants can stay in dappled shade for two to three hours, but no more.
Extend the time by another hour to an hour and a half the next day. If you have a patch of ground that receives morning or evening sun, but is in dappled shade for the heat of the day, this is the best spot to shift to hardening them off on the 6th day when they will be staying outdoors all day.
By the eight or ninth day, start placing them in the area of the garden they will be planted in for the later half of the day, still pulling them indoors at night.
By the thirteenth day, you can leave them in their garden spot all day, and all that night. Water well on the fourteenth day, in their pots, and plant out on the fifteenth day.