Despite this week’s chilly nights, spring is officially here and gardening season has begun!  New birds and wildflowers are appearing almost daily while rhubarb and daffodils have come to life.  The previous article described some early pruning and fruit tree protection techniques that should be done and it’s still a good time for those important tasks.  In this week’s topic, starting your own garden plants from seed assures you get better varieties and it’s very satisfying to grow your own plants from seed to fruit or flower.  Now is the best time to get certain seeds started indoors and this article offers some simple home options to begin your favorite garden plants.  

Most garden soils are still too wet and cool for direct planting but if you have raised beds you can get a head start now.  Raised beds will drain better and warm faster than flat areas so you might try a few very early plantings.  I’ll describe some options for and advantages of raised beds in the next article.  Are you ready for some early spring green salads?  I’ve had good luck with cold tolerant greens such as kale, arugula, leaf lettuces, and mesclun mixes.  These all germinate best when seeds are sown in a gently roughed surface area (Not dug or tilled), lightly covered with a sprinkling of potting soil, and watered with a sprinkling can.  Sunlight warms them and triggers quicker germination so don’t cover them with too much soil or mulch.

Start your seeds indoors.   There are many ways to start seeds successfully; these are my suggestions but let me know your best ideas. Many annual plants (tomatoes, peppers, etc.) need about 6-8 weeks of growth to be in best condition for transplanting in May-June so let’s get them going.  Early broccoli, cauliflower, cabbage, zinnias, marigolds, etc. also can be started in mid-late April.  Plants that only need a 4 week head start (cukes, squash, greens, peas, etc.) should be started later.

First things first.  Your seedlings have 4 basic needs to become healthy plants ready for transplant: 1) soil, 2) light, 3) warmth, & 4) water.  Containers can be almost anything, small pots, 4/6-packs saved from previous purchases, paper/plastic cups, or open trays.  It’s Important that they will last for at least 6-8 weeks of watering and can drain.  Peat pots & cow pots are biodegradable but tend to dry out so you have to watch them.  Soil blocks are a great way to avoid any containers and work well.  Place your containers in a water tight tray so you can water from the bottom (not the top) and catch surplus water.

1. Soil. Seeds will grow best is a very light soil-less seed starting mix.  I don’t recommend standard “potting mixes” or garden soil (too heavy).  Quality starting mixes come very dry in the bags.  Moisten the dry mix well in a large (5 gallon) bucket several hours before filling your containers so it’s thoroughly moist and isn’t fluffy or dusty.  A squeezed handful should hold together.  Fill your containers inside your bucket or tray (less messy) and by gently packing in the soil with your thumbs. Fill so the soil is level with the top (depressions will hold humidity that promotes damp off mold).  Plant seeds according to the package instructions (usually ¼ in. deep).  I plant 2 seeds per cell/pot when using last years seeds with lower germination rates just to be sure I get at least one plant per cell.  Extra seedlings can be culled or moved to empty spaces.
2. Light. If you have enough space in south facing, sunny windows you can use that but additional light will produce better growth.  Florescent fixtures with cool white or full spectrum grow light bulbs work well.  Newer LED fixtures are even better but still pricey.  As bright as they seem, florescent fixtures are much weaker than natural sunlight so the bulbs need to be within 4-6 inches of the plants.  An adjustable plant stand is really useful and there are several very economical (less than $25) DIY design using PVC pipe that accommodates 1-4 full large flats available online.  (See the image below) Seedlings will need 14-16 hours of light per day so a timer is helpful. 
3. Warmth. Unless your home is kept very warm, it is really helpful (but not required) to have a source of warmth under your containers for vigorous germination.  Heat mats for germination keep the soil about 20 degrees warmer that the air and are a worthwhile investment.  They are available from many garden centers and online, cost about $25, and last several years with care (don’t fold them!).  Your heating pad for sore muscles are probably much too warm and not water resistant so not recommended.  Your mat can be removed after full germination has occurred (usually 7-10 days) and used for the next tray of seeds.
4. Water.  If your soil mix was well moistened before filling your containers you probably won’t need to water again until the seeds emerge.  The easiest way to keep the soil moist and warm during germination is to place a clear plastic cover over your trays.  Once you see about half (50%) of the seeds up you should remove your cover so the soil surface can dry out periodically.  I like to avoid disturbing the delicate seedlings by watering from the bottom and letting the water soak up from below to keep the surface from being so wet that surface molds (damp off) get started and kill the young seedlings.  About ¼ inch of water in the bottom tray each watering will suffice and be sure that your trays are sitting level so the water reaches all containers equally. 

Lastly, but very important… be sure to LABEL all of your plants!  Write the date planted and the specific plant & variety or color on your label with a pencil or waterproof ink.  Things get moved around and it’s hard to tell what is what 2 months later.  Of course, enter all your plantings (dates, varieties, how many, etc.) in your garden journal.

What are you planning for your garden?  What are your favorite springtime tips?  Got questions?  Suggestions? Leave a message in the Comments below.