The DTE Notebook for the Urban Organic Vegetable, Herb and Flower Gardener.
Succession planting to get the most out of your garden.
Article and photos by Rob Danforth
Succession planting simply means one planting follows another. Garden space is left unplanted and available for these subsequent plantings. The simplified version of succession planting is planting the same kind of plant (e.g., patty pan squash or bush beans), every 2 weeks to overlap maturation times for continuous production in available garden spaces.
Rationale: Stagger the planting times of
- young plants that are harvested often (e.g., leaf lettuce & mesclun; bush beans – 3 harvests per bush but each harvest with diminishing good taste).
- plants that are naturally short lived due to climate stresses (e.g., cilantro & some Chinese greens are quick to bolt in the hot sun; biennials like parsley, chard, and kale bolt quickly in the 2nd year).
- plants that bugs have savaged, because a second planting may have better results (e.g., early potato plants ravaged by the Colorado Potato beetle could be followed by a mid-June potato planting which will avoid the winged adults depositing eggs). Note: potato is a favourite for the Colorado beetle, but it also likes tomato, eggplant, and pepper plants.
Simplified versus modified succession planting – If you are succession planting for the first time, the simplified version is the best starting point. For the experienced gardener, a schedule can be adapted to the climate and to your usage: some plantings could be in one-week intervals, and some could be in more than two. There is also a limit to the number of successions you can plant depending on your resources (e.g., polytunnels) and the maturation times of plants (e.g., beefsteak tomatoes: 100+ days), because plants may run out of time or of significant sun.
Succession planting can also include replacement plantings to get maximum use of your garden soil throughout the season. Replace failed seed or fallen plants as well as harvested plants with new plantings so garden space is not left to bare soil, which Nature will soon cover in greenery you may not like.
- Stagger plant the following: Basil, Beet greens, Bush beans (green and/or yellow, 3-4 plantings), Chinese greens, Cilantro (sun screened), Dill, Leaf lettuce (sun screened), Mesclun, Mustard greens (harvest young – older leaves have a much stronger taste), and Radish (mild French breakfast radish recommended). Reminder: to do this, you must have extra pots or vacant garden spaces reserved for these plantings. Note: vacant soil spaces can be covered in mulch to suppress weeds until you are ready to use the spaces.
- Replacement planting: in addition to planting the same again, you can also consider relocating flowers and herbs, rooted cuttings (e.g., mint), volunteer plants springing up from your compost (e.g., tomato, squash), and hoarded seedlings from a cold frame or polytunnel (i.e., insurance seedlings you kept back or seedlings you could not bear to destroy). Fill those garden vacancies!
Not very practical for succession in small garden spaces, but you can experiment:
- Some take a full season to mature and succession plants might run out of time: beets, cabbage, carrots, cauliflower, corn, eggplant, garlic, head broccoli, head lettuce, melons, okra, onions, peppers, pole beans, tomatoes, winter squash (e.g., acorn, butternut, spaghetti …).
- Some produce continually, so why bother with succession (e.g. chard, cherry and grape tomatoes, cucumber, kale, parsley, sprouting broccoli, culinary herbs).
- Some are very slow to grow (e.g., all woody stem plants including rosemary, sunflower, and corn).
- Some are heat intolerant and need cold weather for best results (e.g., spinach & pea family)
- Some are invasive and need to be strictly controlled (e.g., mint, strawberries, Japanese anemone, comfrey, …). However, you could use containers and place them in the vacant spots – sink the pot into the soil (closed pots for invasives) or allow decorative pots sitting on the soil to add to the look of your garden.
Planning Information needed
Essential – see seed packages or on-line catalogues for detailed information:
- Germination and maturation times (e.g., match the times to the length of the growing season – Ottawa has 152 days on average – radish can be 30 days, but beefsteak tomatoes can take 100 + days)
- Water needs (e.g., wet & dry cycles for Mediterranean herbs, versus continually moist soil for lettuce, tomatoes, and vine plants)
- Heat/cold/shade tolerances (e.g., tomatoes like heat, spinach prefers cold, and herbs are semi-shade tolerant)
- Plant size at maturity (e.g., lettuce is short and a good filler; tomatoes are tall and can branch widely if not restrained; radish needs very little room; cabbage, Brussel sprouts and broccoli need quite a bit of elbow room).
- Sun requirements (e.g., portulaca needs full sun, tomatoes prefer moderate sun, salad greens need weak sun).
- Length of stay: Annual (e.g., carrots, beans, onions), biennial (e.g., chard, kale, parsley, kohlrabi), or multi-year perennial (e.g., mint, oregano, thyme)
- Companion plants (e.g., friendly, unfriendly, protective, &/or supportive)
Sample put together:
Basil & Tomatoes – both prosper
Dill or Sage & Cabbage family — attracts predator wasps and both prosper
Radishes or Nasturtiums & Leafy greens — attract leaf miners away from greens
Tansy & Brassicas – attract predatory insects (i.e., helpful bugs that eat harmful bugs)
Corn, Beans, & Squash – “3 sisters” symbiosis (corn supports pole beans, beans add nitrogen to the soil, and squash shades out the weeds to limit competition for nutrients).
Garlic, Cleome, Geraniums, Marigolds (African & GEM) & garden plants – smell discourages or masks fragrance of vegetables to protect them from marauding insects.
Goldenrod (yes, an attractive native weed!) & Garden plants – attracts soldier beetles that eat aphids and other bugs.
Sample keep apart: Beans, Peas, & Cabbage family from Onions & Garlic; Dill from Carrots; Potatoes from Tomatoes; Sage from Cucumber; friendly to all: lettuce; unfriendly to all: fennel
Note: the effects of companions are subtle & not immediately noticeable! Don’t hold your breath! Also, experiment for yourself, as sources do not all agree on the exact companions, and sometimes companionship is affected by other gardening variables. My favourites are basil & tomatoes and sage & brassicas – the companions benefit each other every time. 2022 experiment – Marjoram + 3 sisters – worked very well as 4 sisters!
Additional Helpful Information
- Your Intended usage (e.g., steady food supply, attract pollinators, experimentation, pest deterrents, cut & come again, seed collection, garden eye candy, ….)
- pH preferences (e.g., acidic soil, pH of 5 or 6, for garlic, onions, & potatoes; neutral pH of 7, for most vegetables, herbs, & flowers; slightly alkaline pH of 7.5, for cabbage, cauliflower, broccoli, kohlrabi, lilac, crocus, clematis, …). Explanation: pH is a 14-point scale measuring the acidity or alkalinity of the soil. Each digit is a 10-fold change in the strength. Potatoes are safe from potato scab in acidic soil and will tolerate a pH of 6 or even 5. Brassicas do best in slightly alkaline soil of pH 7.5. A gardener can change the pH but never overnight. To keep matters simple and uncomplicated, most gardeners aim for a pH of 7 – compost and composted manure will help achieve this. Note: agricultural lime reduces acidity and garden sulphur increases it, but it is far too easy to overdo it with these amendments and create additional headaches, because the levels of acidity and alkalinity fluctuate depending on weather and time, which is why I found that overdoing it with chemicals is not only possible but quite probable! Do-it-yourself, home-grown compost twice a season is the magic that has worked for us for 45 years.
- Soil conditions (e.g., sandy, heavy clay, rocky, silty, …) Carrots grow well in sandy soil, rhubarb in rich friable soil well drained and well fertilised. Heavy clay is rich in nutrients, does not drain well, sticks to your tools, and is a challenge for plants to penetrate (e.g., carrots will twist and fork) and for gardeners to work. Note: good “garden soil” is a gardener-made (distinct from ground soil), friable (loose & workable), well-draining mixture of clay, sharp sand, and organic matter (i.e., compost – especially do-it-yourself compost where you control the content — or composted manure).
- Rotation plan for all gardens in which the same soil is reused year after year, in order to offset soil problems: nutrient depletion, as well as bugs & diseases in the soil. For urban food gardeners, a rotation schedule of 3 years is recommended (e.g., heavy feeders such as corn, tomatoes and vine plants [generally, the larger the plant and fruit it produces, the heavier the feeding], followed by moderate feeders such as root crops like carrots, turnips, and daikon, followed by legumes such as pea family, beans, and soybeans). No rotation is needed if you plant in portable containers with new soil every year or with ⅔ reclaimed potting soil and ⅓ compost by volume. However, used potting soil must be discarded if diseases were present during the season.
Massive plantings on an end of May weekend in which all soil space is prepared and planted is physically and mentally stressful for gardeners, and not the best for successful food gardening. Give yourself a break, make a plan, and try succession planting. This way you can work at a comfortable pace and enjoy the healthy effort and activity that goes with gardening, as well as the fruits of your labour. Slow and steady reduces stress and makes for happy gardening!